By Lambert Strether of Corrente.
My most frequent Google use case is searching for posts I know I have written so I can link to them, since searching for them on WordPress causes timeouts, because our database has issues.
Imagine my surprise, then, when yesterday (Sunday, February 28), I searched for the following post from February 18, “CDC School Reopening Guidance Suppresses Aerosols Based on Thin Evidence and Driven by Budgetary Concerns,” (Reopening Guidance) and nothing came up. I then performed a number of other searches for likely keywords, like “aerosol.” Again, no joy. I mentioned this to Yves, who also got no hits, and she said I should check with others, since Google will optimize searches for the individual. I verified that “CDC School Reopening Guidance Suppresses Aerosols” at NC was the first hit on both Bing and DuckDuckGo, sent out my want list for searches to two geographically distributed friends, and sat back to await results in the form of screen shots. I present the results here in tabular form, because a post full of screenshots would not be readable:
Table 1: Google Searches for Reopening Guidance February 28 (Three Users)
| Label | Search | Hits for Post |
| #1 | “CDC School Reopening Guidance Suppresses Aerosols” site:www.nakedcapitalism.com | 0 |
| #2 | CDC schools site:www.nakedcapitalism.com | 0 |
| #3 | CDC guidance site:www.nakedcapitalism.com | 0 |
| #4 | walensky site:www.nakedcapitalism.com | 0 |
| #5 | cdc school re-opening site:www.nakedcapitalism.com Sidebar | 0 |
| #6 | aerosols site:www.nakedcapitalism.com | 0 |
So, nobody got results for Reopening Guidance, including search #1, on a big chunk of the post title plus the URL for the site.
Now, in the headline I said that Google “suppressed” Reopening Guidance. (I don’t say “censor,” because in my view censorship is properly considered a function of the State, a task of officialdom, and Google is not a State actor, at least not yet.) There are three reasons (besides past behavior) to think that Google did this. When I searched on “CDC School Reopening Guidance Suppresses Aerosols” (search #1, Table 1):
(1) Reopening Guidance was the very first hit in Bing and DuckDuckGo (each of which run search engines independent of Google). That would imply that Google, and only Google, has some secret sauce that causes my post not to appear.
(2) Reopening Guidance appears in “Recent Items” hits (and one internal cross-reference) but there are no hits for the post itself. Here is a screen shot that shows what I mean:
The red arrows point to hits on Reopening Guidance that can only have come when Google crawled the site and scanned the “Recent Items” list at the top of the post. (That’s why the the third hit is for February 8, before Reopening Guidance was published; the Recent Items list, however, is updated dynamically for all sites. So Google picked it up.) The blue arrow points to a cross-reference, where Reopening Guidance inside a link in another post. So Google is not suppressing the string “CDC School Reopening Guidance Suppresses Aerosols” as such; rather, Google is suppressing any links to a post where “CDC School Reopening Guidance Suppresses Aerosols:” is in the title. That’s some secret sauce Google as got there.
(3) The third reason is even more interesting. Before I started to write this post, I, being an onerous and suspicious person, ran search #1 again. I will again present the results in tabular form:
Table 2: Google Searches for Reopening Guidance March 1 (One User)
| Label | Search | Hits for Post |
| #1 | “CDC School Reopening Guidance Suppresses Aerosols” site:www.nakedcapitalism.com | 1 |
BWA-HA-HA-HA-HA! Now the hit for Reopening Guidance is right where it should be, up top! The thing is, though, I had three people do this search for me yesterday, and the results then are given in Table 1: Zero hits. (Cf. the bloody thumb print in the Sherlock Holmes story, “The Adventure of the Norwood Builder“). So what changed? Google spilled the secret sauce and smeared it all over everything when they tried to clean it up? Impossible to know.
What this little episode does prove is that there is some agent at Google that ranks and unranks posts and sites, and that this agent has nothing to do with finding content (although it may be ensuring that content is not found). I don’t know whether this agent is human or algorithmic, but it’s certainly odd that Google, which will give me a hit on a post seconds after I’ve hit the Submit button for it, has an algo that operates on an hourly, or even a weekly schedule.
Here is the post once more. (Both CDC and WHO have released additional guidance on ventilation and aerosols, which I will examine in due course.)
CDC School Reopening Guidance Suppresses Aerosols Based on Thin Evidence and Driven by Budgetary Concerns
The CDC, newly headed by Biden appointee Rochelle Walensky, has issued guidance on school re-opening. From the Associated Press:
The Centers for Disease Control and Prevention released its long-awaited road map for getting students back to classrooms in the middle of a pandemic that has killed nearly 480,000 people in the U.S. But the agency’s guidance is just that — it cannot force schools to reopen, and CDC officials were careful to say they are not calling for a mandate that all U.S. schools be reopened.
Officials said there is strong evidence now that schools can reopen, especially at lower grade levels….
The guidance was issued as President Joe Biden faces increasing pressure to deliver on his promise to get the majority of K-8 schools back to in-person teaching by the end of his first 100 days in office. He acknowledged that the goal was ambitious, but added, “It is also a goal we can meet if we follow the science.”
This post will follow the science; it’s an open question, however, whether CDC did, as we shall see. There are two key documents:
1) Operational Strategy for K-12 Schools through Phased Mitigation (“Strategy“) (updated Feb. 12, 2021), which provides guidance to the schools, and
2) Transmission of SARS-CoV-2 in K-12 schools (“Transmission“) (updated Feb. 12, 2021), which documents “the science” upon which the guidance is (putatively) based. (Readers may wish to jump to the Appendix, where Table 2 lists, categorizes, and provides quotations from the 61 sources cited in Transmission. Scanning the quotations may provide an approximation of the science as CDC understands it, at least with respect to Covid, schools, and children. I will use select citations from Table 2 in Table 1, when I take a look at CDC’s use of epidemiogy.)
There are two central issues with Strategy. The first might be labeled its Central Dogma. The second is the action items in Strategy. Here is the CDC’s Central Dogma:
The occurrence of SARS-CoV-2 infection in schools reflects transmission in the surrounding community.
That is, schools themselves are not drivers of transmission, but rather, as it were, passive recipients of it. This is certainly disputable, for example in this recent thread on Montréal:
6) Dr. Drouin noted that Montreal schools have become a driving force in the spread of the #coronavirus since reopening last month, blaming them for the increase in #COVID19 cases among the 0-to-17 and 35-to-44 age demographics, the latter being parents.
— Aaron Derfel (@Aaron_Derfel) February 11, 2021
See also this recent thread on the UK:
A few things to note:
1. The infection rates among primary & secondary school children closely follow school openings, closures & levels of attendance. E.g. We see a dip in infections following Oct half-term, followed by a rise after school reopening. pic.twitter.com/dqyfAhtPPu— Deepti Gurdasani (@dgurdasani1) February 18, 2021
I will have more to say about reasoning from other countries to this one later in the post. But for now, consider these two tweets as prima facie evidence that the CDC’s Central Dogma is open to question. We will pass on from that topic to the central focus of this post: The CDC’s action items. From Executive Summary of Strategy, here they are:
You will notice immediately that aerosol transmission is omitted; the message of Strategy is that aerosol transmission can be ignored because it is not an “essential” element. This message is getting through; from an acute summary of Strategy in WaPo, “The CDC’s plan to reopen schools seems to prioritize expediency over teachers’ health“:
Here’s what the guidance does well. Unlike the Trump administration’s watered-down recommendations that were couched in language such as wearing masks “if possible,” these new guidelines are clear on many points. They lay out five mitigation measures that every school should implement: masking, distancing, hand-washing, cleaning and contact tracing. The part I like the most is how the CDC has divided schools into four categories based on degree of covid-19 transmission in their surrounding communities. At low and moderate levels, full in-person learning can occur; at higher levels, hybrid or reduced attendance is recommended.
Again, the CDC’s “mitigation strategies” omit discussion of aerosol entirely (even to ventilation). Frankly, I was gobsmacked. I hate to deploy terms like “criminal malpractice,” so I won’t, but such was my level of gobsmacked-ness. Further, if you accept, as I do, the SARS-COV-2 can be transmitted by aerosols, the CDC Transmission document — “the science” backing up the recommendations — rests on a very modest epidemiological base. Let’s consider first the CDC’s suppression[1] of aerosol transmission.
The CDC Suppresses Aerosol Transmission: Why?
First, let’s define our terms. From an excellent article in Journal of Hospital Infection, “Dismantling myths on the airborne transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)“:
There is little doubt that SARS-CoV-2 is transmitted via a range of airborne particle sizes subject to all the usual ventilation parameters and human behaviour. To clarify the terminology used in this article, therefore, droplets are particles that fall to the ground (or any surface including vertical surfaces) under the influence of gravity and/or the momentum of an infected person’s exhaled air; and aerosols are particles that remain suspended due to size and/or environmental conditions.
I would summarize this by saying that particle behavior is what matters, not arbitrary size constraints. Aerosols float, like cigarette smoke. Droplets are ballistic; they fall, like tiny loogies. Hence, whenever you hear somebody advocating a distance measure, like the six feet recommended by Strategy, you’re hearing someone protecting against droplets, but not aerosols, because aerosols can float for long distances. Aerosols, again like cigarette smoke, gradually fill up any closed space into which they are emitted. El Pais has an especially vivid discussion of this in “A room, a bar and a classroom: how the coronavirus is spread through the air“:
(The figures are based on the Covid Airborne Transmission Estimator developed by a group of scientists led by Professor José Luis Jiménez from the University of Colorado.) I saw that El Pais article cited innumerable times on the Twitter by people reacting to CDC’s aerosol-suppressing guidance, so I imagine at some point the CDC and the White House will become aware of it.
Now, to be fair, aerosol vs. droplet transmission has been a bit of a paradigm shift for the public health community (con vs. pro)[2]. However, until CDC Strategy came out, I had thought that aerosol transmission was settled science; that the shift had occurred. El Pais once more:
In the spring, health authorities failed to focus on aerosol transmission, but recent scientific publications have forced the World Health Organization (WHO) and the CDC to acknowledge it. An article in the prestigious Science magazine found that there is “overwhelming evidence” that airborne transmission is a “major transmission route” for the coronavirus, and the CDC now notes that, “under certain conditions, they seem to have infected others who were more than six feet [two meters] away. These transmissions occurred within enclosed spaces that had inadequate ventilation. Sometimes the infected person was breathing heavily, for example, while singing or exercising.”
Now, however, the CDC is backsliding; of the many institutions and publications supporting aerosol transmission I”ll pick Harvard’s T. H. Chan School of Health, since Walensky is surely familiar with it:
4/ The decision to open schools is complex, controversial, & emotional. Everyone wants students & teachers to be safe. The gist of all reputable reports on school re-opening is a layered approach, but critical to address the airborne component of spread. https://t.co/aQTHnv57w7
— Dr. Alex Huffman (@HuffmanLabDU) February 13, 2021
But why the backsliding? (Walensky’s message discipline is such that she didn’t mention either aerosols or ventilation in her interview on Face the Nation.) I believe the answer is to be found in the source cited in the very first footnote of our second document, Transmission. From The National Academies of Sciences, Engineering, and Medicine, “Reopening K-12 Schools During the COVID-19 Pandemic: Prioritizing Health, Equity, and Communities,” at section “The Role of Airborne Transmission of COVID-19“:
In the process of writing this report, the committee repeatedly returned to conversations around the role of airborne transmission of COVID-19. As described in Chapter 3, indoor air quality in U.S. public schools is notoriously poor, which can have innumerable deleterious health impacts on students and staff. However, because there is not yet scientific consensus on the role of airborne transmission in the spread of the virus, it is also unclear how the indoor air quality of schools matters in the spread of COVID-19. Given the considerable cost associated with updating aging facilities, it is particularly important to understand the exact role of airborne transmission such that stakeholders can assess the relative value and utility of that investment.
Needless to say, this is a budgetary — hence political — constraint, not “the science.” Nor could it be! And sadly, by reducing the question of aerosol transmission and indoor quality to facilities they enable the CDC to deny children, parents, and teachers simpler methods of mitigation:
5/ Zilch on use of single-zone portable HEPA air filters to supplement ventilation, boost equivalent ACH, or help reduce concentrations of aerosol particles when students are out of room, which lowers levels on return & can signif' lower daily dose. Incredibly disappointing.
— Dr. Richard Corsi (@CorsIAQ) February 13, 2021
Shoddy work all round.
The CDC’s Epidemiology Is Weak
Now let us turn to “the science,” as presented in Transmission. Let me explain why, while I respect the other methods of scientific work being done Covid — statistical work, aggregater reports, metastudies, and miscellaneous narratives — I find epidemiological studies — wiht index cases, seating diagrams, contact tracing — essential. For a policy maker, no doubt all the methods listed are important. But for me as an individual, they are not enough. A metaphor may help. For a World War I General asking his soldiers to go “over the top,” a likely casualty rate will have informed his decision. But the soldier needs to know the actual ground; where the barbed wire is, when to duck the machine gun fire, etc. With Covid, I would want to know the actual ground, too, no matter the odds: For example, I know it makes no sense to sit downwind from an air conditioner in a closed space, even if it makes sense to enter the closed space in the first place. Only “shoe leather” epidemiology can provide such answers. For example, I would certainly want to know whether the windows in my child’s classroom could be opened, if they can be, whether they are.
However, epidemiology, being of the ground, is necessarily localized and not global. For example, here is a description of schooling in Norway from an American who spent a year as a teacher there.
After every 45 min or so of lessons, students spend 10 to 15 minutes playing outside or in common areas– as many as five or six times a day. At many schools teachers hold on to the students’ cell phones all day in a “cell phone hotel” and encourage real play during break times, like a short pick-up game of soccer or foosball or just jumping around with friends for a few minutes. And during this time, someone always opens a window to let in a little fresh air, even in December.
Obviously, that’s a well-ventilated school (and one that dilutes any aerosols that are to be found). And yet, I doubt very much whether any of the global, statistical work that includes data from Norway takes these facts on the ground into account. How would they now? And yet, given that aerosol transmission is “the science,” those facts are essential. With that in mind, let us look at all the epidemiological studies in Transmission, extracting the relevant rows from Table 2 in Appendix 1:
Table 1: Epidemiological Sources in CDC’s Transmission of SARS-CoV-2 in K-12 schools
| 45 | Finland | Epi | School | Art | Ot | 07/30/20 | Transmission of SARS-CoV-2 following exposure in school settings: experience from two Helsinki area exposure incidents. Preprint. MedRxiv |
| When the index was a child, no school transmission was identified, while the occurrence of an adult case led to a 16% AR. Further cases were evidenced in 3 families, but other transmission chains were plausible. It is likely that transmission from children to adults is limited. | |||||||
| 60 | France | Epi | Choir Room | Art | Fi | 12/23/20 | High Rate of SARS-CoV-2 Transmission Due to Choir Practice in France at the Beginning of the COVID-19 Pandemic. J Voice. |
| The characteristics of the viral transmission via close human contacts was probably enhanced by the act of singing, at a phase of intense circulation of SARS-CoV-2 in the population at this period. We report in our study the role of asymptomatic infection carriers initiating a silent chain of transmission of the coronavirus, leading to a cluster under the circumstances of the rehearsal. This study confirms that the transmission of the virus from asymptomatic cases is very efficient. | |||||||
| 41 | Germany | Epi | School/ECOC | Art | Fi | 09/10/20 | Transmission of SARS-CoV-2 in children aged 0 to 19 years in childcare facilities and schools after their reopening in May 2020, Baden-Württemberg, Germany. Euro Surveill. |
| Child-to-child transmission in schools/childcare facilities appeared very uncommon. We anticipate that, with face mask use and frequent ventilation of rooms, transmission rates in schools/childcare facilities would remain low in the next term, even if classes’ group sizes were increased. | |||||||
| 23 | Israel | Epi | Household | Art | Fi | 08/2020 | The Role of Children in the Dynamics of Intra Family Coronavirus 2019 Spread in Densely Populated Area. Pediatr Infect Dis J. |
| Our investigation demonstrated significantly lower rates of COVID-19 positivity in children compared with adults residing in the same household. | |||||||
| 36 | Israel | Epi | School | Art | Fi | 07/23/20 | A large COVID-19 outbreak in a high school 10 days after schools’ reopening, Israel, May 2020. Euro Surveill |
| The high school outbreak in Jerusalem displayed mass COVID-19 transmission upon school reopening. The circumstances promoting infection spread involved return of teenage students to their regular classes after a 2-month closure (on 18 May) and an extreme heatwave (on 19 May) with temperatures rising to 40 °C and above [6] that involved exemption from facemasks and continuous air-conditioning. | |||||||
| 48 | Italy | Epi | School/ECOC | Art | Fi | 12/2020 | Secondary transmission of COVID-19 in preschool and school settings in northern Italy after their reopening in September 2020: a population-based study. Euro Surveill |
| The overall secondary case attack rate was 3.2%, reaching 6.6% in middle and high schools. More timely isolation and testing of classmates could be effective in reducing virus transmission in this setting. | |||||||
| 52 | Norway | Epi | School | Art | Fi | 01/2021 | Minimal transmission of SARS-CoV-2 from paediatric COVID-19 cases in primary schools, Norway, August to November 2020 |
| This prospective study shows that transmission of SARS-CoV-2 from children under 14 years of age was minimal in primary schools in Oslo and Viken, the two Norwegian counties with the highest COVID-19 incidence and in which 35% of the Norwegian population resides. | |||||||
| 40 | Singapore | Epi | School/ECOC | Art | Fi | 06/25/20 | Novel coronavirus 2019 transmission risk in educational settings. Clin Infect Dis. |
| The data suggest that children are not the primary drivers of SARS-CoV-2 transmission in schools and could help inform exit strategies for lifting of lockdowns. | |||||||
| 55 | South Korea | Epi | Fitness Center | Art | Fi | 05/15/20 | Cluster of Coronavirus Disease Associated with Fitness Dance Classes, South Korea. Emerg Infect Dis. 2020 |
| During 24 days in Cheonan, South Korea, 112 persons were infected with severe acute respiratory syndrome coronavirus 2 associated with fitness dance classes at 12 sports facilities. Intense physical exercise in densely populated sports facilities could increase risk for infection. | |||||||
| 56 | South Korea | Epi | Fitness Center | Art | Fi | 08/10/20 | Epidemiological Characteristics of COVID-19 Outbreak at Fitness Centers in Cheonan, Korea. J Korean Med Sci |
| Zumba is an exercise fitness program which combines aerobic exercise with music, and Oriental and Latin dance moves.5 In the fitness centers where the Zumba classes were held, a large number of students had taken classes in a relatively crowded space, although ventilation systems were working properly. … [T]he droplets produced by exhalation or cough of a patient during the exercise have higher chance of reaching the nose, mouth or eye of other class participants directly, as well as remaining on the surface of the exercise equipment and later transmitted by contact. | |||||||
| 57 | US, FL | Epi | School Gym | Art | Fi | 10/16/20 | An Outbreak of COVID-19 Associated with a Recreational Hockey Game — Florida, June 2020. MMWR Morb Mortal Wkly Rep |
| The study was unable to determine exactly where exposure occurred, but hypothesizes it was at the evening hockey game, due to the heavy breathing that occurs, the lack of masks covering the mouth and nose, the transition from ice to bench where players continue heavy breathing or in the locker rooms and lack of other common exposures or time spent together. | |||||||
| 58 | US, FL | Epi | School Gym | Art | Fi | 01/26/21 | SARS-CoV-2 Transmission Associated with High School Wrestling Tournaments — Florida, December 2020–January 2021. MMWR Morb Mortal Wkly Rep |
| An outbreak arising from a Florida high school wrestling tournament in December 2020 had an attack rate of at least 30% (38 of 126 tournament attendees who were tested) and a secondary attack rate of at least 9% (41 of 441 close contacts of the 38 COVID-19 patients) | |||||||
| 39 | US, NC | Epi | School | Art | Pr | 1/2021 | Incidence and Secondary Transmission of SARS-CoV-2 Infections in Schools. Pediatrics. |
| In the first 9 weeks of in-person instruction in North Carolina schools, we found extremely limited within-school secondary transmission of SARS-CoV-2, determined by contact tracing | |||||||
| 59 | US, WA | Epi | Choir Room | Art | Fi | 05/15/20 | High SARS-CoV-2 Attack Rate Following Exposure at a Choir Practice — Skagit County, Washington, March 2020. MMWR Morb Mortal Wkly Rep. |
| Transmission was likely facilitated by close proximity (within 6 feet) during practice and augmented by the act of singing. | |||||||
You will observe there are 14 epidemiological cases in all. Recalling the example of Norway above, we throw out all the examples except those from the US. Four remain, which I have helpfully highlighted. Two are gyms, which are nothing like classrooms in their patterns of ventilation, both in Florida (!). One is a choir room, ditto. One remains.
Therefore, as far as school re-opening classroom epidemiology in the United States goes, Transmission depends on one case. Transmission is an enormous inverted pyramid whose apex is a single point. I have to say that balancing act doesn’t fill me with confidence.
Conclusion
Politico summarized the CDC’s reopening strategy in “Biden’s follow-the-science mantra on school meets political reality“:
Biden administration officials insist that the White House is grounding all of its policy decisions firmly in the best available evidence. They say the president receives a daily state of pandemic update from his Covid response team in his daily briefing book. And indeed, the Biden administration has taken care to give health experts like Anthony Fauci and CDC Director Rochelle Walensky leading roles in managing the response, and solicited constant input from its health agencies and outside public health groups.
Well, no. The budgetary concerns of “stakeholders” aren’t science, aren’t a mantra, and aren’t evidence, either. If Biden’s response team isn’t including aerosols and ventilation in his briefing books (the same issue occurs in other contexts) I want to know why. Ditto for soliciting constant input, because it doesn’t look like CDC reached out to aerosol experts at all. And then Politico continues:
Biden transition officials spent weeks crafting plans for safely reopening schools based on public health best practices, including proposing a massive new Covid testing regime and hundreds of billions of dollars in funding to help retrofit classrooms and overhaul ventilation systems.
No, they didn’t, because without taking aerosol tranmission into account, you don’t have best practices; you have tepid guidance like opening windows “to the extent possible.” But even more weirdly, if overhauling ventilation systems is going to be a line item in the budget, why in the name of all that is holy did CDC carefully suppress aerosols from its guidance? Or fail to do any serious epidemiological work on it?
The CDC already has two strikes against it: It catastrophically butchered the test kit rollout[3], and it butchered the software development for VAMA (the Vaccine Administration Management System). Now Walensky whiffs on school re-opening. Is that strike three? It’s hard to avoid the conclusion that the CDC is completely dysfunctional, and that Walensky, despite her warm personality, is unlikely to have the administrative and institutional chops to fix what’s wrong.
NOTES
[1] The CDC does mention ventilation in its “Health Facilities” section: “Improve ventilation to the extent possible such as by opening windows and doors to increase circulation of outdoor air to increase the delivery of clean air and dilute potential contaminants.” Sounds discouraging. Nor is aerosol tranmission mentioned. Why then open the windows?
[2] Here is an entertaining thread on the history of droplets v. aerosols from that same Professor Jiménez.
[3] Of the many shifting stories, here is the latest.
APPENDIX
Table 2: Complete Sources in CDC’s Transmission of SARS-CoV-2 in K-12 schools
Legend:
The Note column keys to the footnote numbers in SARS-CoV-2 in K-12 schools.
Abbreviations by column: Method: Model, Statistical, Epidemiological, Aggregation, Metastudy Narrative; Type: Article, Editorial Letter Revview Study Status: Preprint, Fininal, Other.
Citations are to linked title and publication only, for space purposes.
Beneath each source row, I’ve placed a quotation taken from that source. Scanning the quotes may give a sense of where “the science” is, as CDC conceives it.
| Note | Country | Method | Venue (Epi. Only) | Type | Status | Date | Citation |
| 1 | — | Agg | Art | Fi | 07/15/20 | Reopening K-12 Schools During the COVID-19 Pandemic: Prioritizing Health, Equity, and Communities. Consensus study report from The National Academies Press. | |
| In its final recommendation, the committee identifies four areas of research that are urgently needed to fill the existing gaps in evidence: (1) the role of children in transmission of SARS-CoV-2, (2) the role of reopening schools in the spread of SARS-CoV-2 in communities, (3) the role of airborne transmission of COVID-19, and (4) the relative effectiveness of different mitigation strategies in schools. | |||||||
| 2 | Nar | Edi | Fi | 07/29/20 | COVID-19 and School Closures. JAMA | ||
| Given the strong connection between education, income, and life expectancy,9 school closures could have long-term deleterious consequences for child health, likely reaching into adulthood. School closures also affect parents’ ability to work. | |||||||
| 3 | Australia | Sta | Art | Fi | 09/25/21 | COVID-19 in Victorian Schools: An analysis of child-care and school outbreak data and evidence-based recommendations for opening schools and keeping them open. Report from Murdoch Children’s Research Institute and the University of Melbourne. 2020; Published 2020 September 25. | |
| Infections linked to [Early Childhood Education and Care (ECECs)] and schools peaked at the time when community transmission was highest during July and then declined in August, suggesting that infections in ECECs and schools are driven primarily by transmission in the broader community. | |||||||
| 4 | US | Sta | Art | Fi | 04/10/20 | Coronavirus Disease 2019 in Children — United States, February 12–April 2, 2020. MMWR Morb Mortal Wkly Rep | |
| [R]elatively few children with COVID-19 are hospitalized, and fewer children than adults experience fever, cough, or shortness of breath | |||||||
| 5 | — | Mod | Let | Fi | 06/16/20 | Age-dependent effects in the transmission and control of COVID-19 epidemics. Nat Med | |
| We estimate that susceptibility to infection in individuals under 20 years of age is approximately half that of adults aged over 20 years, and that clinical symptoms manifest in 21% (95% credible interval: 12–31%) of infections in 10- to 19-year-olds | |||||||
| 6 | China | Sta | Art | Fi | 03/16/20 | Epidemiology of COVID-19 Among Children in China. Pediatrics | |
| Children of all ages appeared susceptible to COVID-19, and there was no significant sex difference. Although clinical manifestations of children’s COVID-19 cases were generally less severe than those of adult patients, young children, particularly infants, were vulnerable to infection. | |||||||
| 7 | US, UT/WA | Sta | Art | Fi | 01/01/21 | Symptoms and Transmission of SARS-CoV-2 Among Children — Utah and Wisconsin, March–May 2020. Pediatrics. | |
| Children and adults had similar secondary infection rates, but children generally had less frequent and severe symptoms. In two states early in the pandemic, we observed possible transmission from children in approximately one-fifth of households with potential to observe such transmission patterns. | |||||||
| 8 | US, UT/WA | Sta | Art | Fi | 01/01/21 | COVID-19 in Children: Looking Forward, Not Back. Pediatrics | |
| In this study, the researchers found that 20% and 17% of households had potential child-to-adult transmission and child-to-child transmission, respectively, but numbers are too small to draw definitive conclusions. | |||||||
| 9 | China | Sta | Let | Fi | 04/23/20 | SARS-CoV-2 Infection in Children.NEJM | |
| In contrast with infected adults, most infected children appear to have a milder clinical course. Asymptomatic infections were not uncommon.2 Determination of the transmission potential of these asymptomatic patients is important for guiding the development of measures to control the ongoing pandemic. | |||||||
| 10 | — | Agg | Rev | Fi | 06/17/20 | Children are unlikely to be the main drivers of the COVID‐19 pandemic – A systematic review. Acta Paediatr. | |
| Children are unlikely to be the main drivers of the pandemic. Opening up schools and kindergartens is unlikely to impact COVID-19 mortality rates in older people. | |||||||
| 11 | — | Agg | Rev | Fi | 12/2020 | COVID-19 in children: current evidence and key questions. Curr Opin Infect Dis | |
| Important questions remain unanswered regarding why children have mild disease compared with adults; how children of different ages contribute to asymptomatic community transmission of the virus; and the pathophysiology of and most appropriate investigation and treatment strategies for the novel hyperinflammatory syndrome. | |||||||
| 12 | — | Agg | Rev | 09/01/20 | Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection in Children and Adolescents: A Systematic Review. JAMA Pediatr | ||
| The rapid spread of COVID-19 across the globe and the lack of European and US data on pediatric patients require further epidemiologic and clinical studies to identify possible preventive and therapeutic strategies. | |||||||
| 13 | — | Agg | Rev | Fi | 04/06/20 | Epidemiology and clinical features of coronavirus disease 2019 in children. Clin Exp Pediatr | |
| This review summarizes what is currently known about COVID-19 in children and adolescents. | |||||||
| 14 | — | Agg | Rev | Ot | 01/12/20 | Why is COVID-19 less severe in children? A review of the proposed mechanisms underlying the age-related difference in severity of SARS-CoV-2 infections. Arch Dis Child. | |
| In this review, we discuss proposed hypotheses for the age-related difference in severity of coronavirus disease | |||||||
| 15 | Europe | Sta | Art | Fi | 06/25/20 | COVID-19 in children and adolescents in Europe: a multinational, multicentre cohort study. Lancet Child Adolesc Health | |
| COVID-19 is generally a mild disease in children, including infants. However, a small proportion develop severe disease requiring ICU admission and prolonged ventilation, although fatal outcome is overall rare. | |||||||
| 16 | US | Sta | Art | Fi | 10/02/20 | COVID-19 Trends Among School-Aged Children — United States, March 1–September 19, 2020. MMWR Morb Mortal Wkly Rep | |
| Underlying conditions were more common among school-aged children with severe outcomes related to COVID-19: among school-aged children who were hospitalized, admitted to an intensive care unit (ICU), or who died, 23%, 38%, and 33%, respectively, had at least one underlying condition. | |||||||
| 17 | US | Sta | Art | Fi | 01/22/21 | COVID-19 Trends Among Persons Aged 0–24 Years — United States, March 1–December 12, 2020. MMWR Morb Mortal Wkly Rep | |
| COVID-19 cases in children, adolescents, and young adults have increased since summer 2020, with weekly incidence higher in each successively increasing age group. | |||||||
| 18 | Iceland | Sta | Art | Fi | 06/11/20 | Spread of SARS-CoV-2 in the Icelandic Population. N Engl J Med | |
| In a population-based study in Iceland, children under 10 years of age and females had a lower incidence of SARS-CoV-2 infection than adolescents or adults and males. The proportion of infected persons identified through population screening did not change substantially during the screening period, which was consistent with a beneficial effect of containment efforts. | |||||||
| 19 | — | Met | Art | Fi | 12/01/20 | Household Transmission of SARS-CoV-2: A Systematic Review and Meta-analysis. JAMA Netw Open | |
| [G]iven that individuals with suspected or confirmed infections are being referred to isolate at home, households will continue to be a significant venue for transmission of SARS-CoV-2. | |||||||
| 20 | China | Sta | Art | Fi | 06/26/20 | Changes in contact patterns shape the dynamics of the COVID-19 outbreak in China. Science | |
| [C]hildren 0 to 14 years of age are less susceptible to severe acute respiratory syndrome coronavirus (SARS-CoV-2) infection than adults 15 to 64 years of age. | |||||||
| 21 | — | Met | Art | Fi | 02/01/20 | Susceptibility to SARS-CoV-2 Infection Among Children and Adolescents Compared With Adults: A Systematic Review and Meta-analysis. JAMA Pediatr. | |
| In this meta-analysis, there is preliminary evidence that children and adolescents have lower susceptibility to SARS-CoV-2, with an odds ratio of 0.56 for being an infected contact compared with adults. There is weak evidence that children and adolescents play a lesser role than adults in transmission of SARS-CoV-2 at a population level. | |||||||
| 22 | — | Agg | Rev | 10/29/20 | On the Effect of Age on the Transmission of SARS-CoV-2 in Households, Schools, and the Community. J Infect Dis | ||
| There is some evidence that given limited control measures, SARS-CoV-2 may spread robustly in secondary/high schools, and to a lesser degree in primary schools, with class size possibly affecting that spread. There is also evidence of more limited spread in schools when some mitigation measures are implemented. | |||||||
| 23 | Israel | Epi | Household | Art | Fi | 08/2020 | The Role of Children in the Dynamics of Intra Family Coronavirus 2019 Spread in Densely Populated Area. Pediatr Infect Dis J. |
| Our investigation demonstrated significantly lower rates of COVID-19 positivity in children compared with adults residing in the same household. | |||||||
| 24 | Italy | Sta | Art | Fi | 06/30/20 | Suppression of a SARS-CoV-2 outbreak in the Italian municipality of Vo’. Nature | |
| The experience of Vo’ shows that, despite the silent and widespread transmission of SARS-CoV-2, transmission can be controlled and represents a model for the systematic suppression of viral outbreaks under similar epidemiological and demographic conditions. | |||||||
| 25 | — | Met | Art | Fi | 12/06/20 | A meta-analysis on the role of children in SARS-CoV-2 in household transmission clusters. Clin Infect Dis. | |
| Children are Infrequently Identified as the Index Case of Household SARS-CoV-2 Clusters | |||||||
| 26 | US, NY | Sta | Let | Fi | 05/20/20 | Nasal Gene Expression of Angiotensin-Converting Enzyme 2 in Children and Adults. JAMA. | |
| [C]ompared with younger children, ACE2 gene expression was significantly higher in older children. | |||||||
| 27 | — | Nar | Let | Fi | 05/06/20 | The immune system of children: the key to understanding SARS-CoV-2 susceptibility?. Lancet Child Adolesc Health. | |
| Children are more vulnerable to other infections; thus, the important question arises—why are children less susceptible to COVID-19 disease compared with adults? So far, there is no evidence of a lower degree of expression or function of the SARS-CoV-2 receptor (namely ACE2) in children. Thus, studying the innate immune system of children might be the key | |||||||
| 28 | US, NY | Sta | Let | Fi | 11/05/20 | Distinct antibody responses to SARS-CoV-2 in children and adults across the COVID-19 clinical spectrum. Nat Immunol | |
| The clinical manifestations of SARS-CoV-2 infection in children are distinct from adults. Children with COVID-19 rarely exhibit severe respiratory symptoms and often remain asymptomatic | |||||||
| 29 | Israel | Sta | Art | Fi | 02/11/21 | The role of children in the spread of COVID-19: Using household data from Bnei Brak, Israel, to estimate the relative susceptibility and infectivity of children. Preprint. MedRxiv | |
| [T]he fraction of children among the confirmed cases has been found to be low in many countries can be accounted for by two (nonexclusive) hypotheses: (1) Children display milder symptoms than adults when infected, so are less likely to be tested in a typical testing policy triggered by symptoms, (2) Children are less susceptible to infection than adults. Our analysis of the data obtained in this study lends support to <em>both</em> hypotheses, and indicates that both have a role in explaining the observed epidemiological patterns. | |||||||
| 30 | South Korea | Sta | Art | Fi | 10/2020 | Contact Tracing during Coronavirus Disease Outbreak, South Korea, 2020. Emerg Infect Dis | |
| Of 10,592 household contacts, 11.8% had COVID-19. Of 48,481 nonhousehold contacts, 1.9% had COVID-19. | |||||||
| 31 | China | Sta | Art | Pr | 07/24/20 | Infectivity, susceptibility, and risk factors associated with SARS-CoV-2 transmission under intensive contact tracing in Hunan, China. Preprint. MedRxiv | |
| Our findings support the hypothesis that children can effectively transmit SARS-CoV-2 and highlight how pre-symptomatic and asymptomatic transmission can hinder control efforts. | |||||||
| 32 | UK | Sta | Art | Fi | 08/24/20 | SARS-CoV-2 infection and transmission in educational settings: a prospective, cross-sectional analysis of infection clusters and outbreaks in England. Lancet Infect Dis | |
| Overall, SARS-CoV-2 infections and outbreaks were uncommon across all educational settings. Staff members had an increased risk of SARS-CoV-2 infections compared to students in any educational setting, and the majority of cases linked to outbreaks were in staff. | |||||||
| 33 | Europe | Sta | Art | Pr | 11/13/20 | Age differential analysis of COVID-19 second wave in Europe reveals highest incidence among young adults. Preprint. MedRxiv | |
| [W]e analyze data of incidence by age groups in 25 European countries, revealing that the highest incidence of the current second wave is observed for the group comprising young adults (aged 18-29 years old) in all but 3 of the countries analyzed. | |||||||
| 34 | Italy | Mod | Art | Pr | 12/18/20 | No evidence of association between schools and SARS-CoV-2 second wave in Italy. Preprint. MedRxiv | |
| [S]chool closures in two regions where they were implemented before other measures did not affect the rate of Rt decline. In schools, despite the high frequency of tests per week, secondary infections were <1%, and clusters in a representative November week infrequent. Thus, our prospective analysis does not support a role for school reopening as a driver of the second wave of SARS-CoV-2 epidemics in Ital | |||||||
| 35 | US | Sta | Art | Fi | 01/04/21 | The Effects of School Reopenings on COVID-19 Hospitalizations. Technical Report from the National Center for Research on Education Access and Choice (REACH). | |
| The study is the first to examine how reopening schools in-person has affected COVID-19 hospitalizations. We found no evidence that reopening schools in-person or in a hybrid form increased COVID hospitalizations in the 75 percent of counties that had low COVID hospitalization rates during the summer, prior to reopening schools. Our results suggest that it seems safe to reopen schools when there are no more than 36 to 44 total new COVID hospitalizations per 100,000 people per week. | |||||||
| 36 | Israel | Epi | School | Art | Fi | 07/23/20 | A large COVID-19 outbreak in a high school 10 days after schools’ reopening, Israel, May 2020. Euro Surveill |
| The high school outbreak in Jerusalem displayed mass COVID-19 transmission upon school reopening. The circumstances promoting infection spread involved return of teenage students to their regular classes after a 2-month closure (on 18 May) and an extreme heatwave (on 19 May) with temperatures rising to 40 °C and above [6] that involved exemption from facemasks and continuous air-conditioning. | |||||||
| 37 | Germany | Sta | Art | Fi | 09/2020 | Surveillance of COVID-19 school outbreaks, Germany, March to August 2020. Euro SurveillSurveillance of COVID-19 school outbreaks, Germany, March to August 2020 | |
| Only few and mostly small COVID-19 school outbreaks had been reported in Germany overall, suggesting that the containment measures are sufficient to reduce spillover into the community. | |||||||
| 38 | US, MI/WA | Mod | Art | Fi | 2/2021 | To What Extent Does In-Person Schooling Contribute to the Spread of COVID-19? Evidence from Michigan and Washington. Report from the Center for Education Data & Research (CEDR), National Center for Analysis of Longitudinal Data in Education Research (CALDER), and Education Policy Innovation Collaborative (EPIC). | |
| Using a variety of regression modeling strategies , we find that simple correlations show in-person modalities are correlated with increased COVID cases, but accounting for both pre-existing cases and a richer set of covariates brings estimates close to zero on average. | |||||||
| 39 | US, NC | Epi | School | Art | Pr | 1/2021 | Incidence and Secondary Transmission of SARS-CoV-2 Infections in Schools. Pediatrics. |
| In the first 9 weeks of in-person instruction in North Carolina schools, we found extremely limited within-school secondary transmission of SARS-CoV-2, determined by contact tracing | |||||||
| 40 | Singapore | Epi | School/ECOC | Art | Fi | 06/25/20 | Novel coronavirus 2019 transmission risk in educational settings. Clin Infect Dis. |
| The data suggest that children are not the primary drivers of SARS-CoV-2 transmission in schools and could help inform exit strategies for lifting of lockdowns. | |||||||
| 41 | Germany | Epi | School/ECOC | Art | Fi | 09/10/20 | Transmission of SARS-CoV-2 in children aged 0 to 19 years in childcare facilities and schools after their reopening in May 2020, Baden-Württemberg, Germany. Euro Surveill. |
| Child-to-child transmission in schools/childcare facilities appeared very uncommon. We anticipate that, with face mask use and frequent ventilation of rooms, transmission rates in schools/childcare facilities would remain low in the next term, even if classes’ group sizes were increased. | |||||||
| 42 | US, WI | Sta | Art | Fi | 01/29/21 | COVID-19 Cases and Transmission in 17 K–12 Schools — Wood County, Wisconsin, August 31–November 29, 2020. MMWR Morb Mortal Wkly Rep. | |
| Among 17 rural Wisconsin schools, reported student mask-wearing was high, and the COVID-19 incidence among students and staff members was lower than in the county overall (3,453 versus 5,466 per 100,000). Among 191 cases identified in students and staff members, only seven (3.7%) cases, all among students, were linked to in-school spread. | |||||||
| 43 | US, MS | Sta | Art | Fi | 12/18/21 | Factors Associated with Positive SARS-CoV-2 Test Results in Outpatient Health Facilities and Emergency Departments Among Children and Adolescents Aged <18 Years — Mississippi, September–November 2020. MMWR Morb Mortal Wkly Rep. | |
| Among children and adolescents aged <18 years in Mississippi, close contact with persons with COVID-19 and gatherings with persons outside the household and lack of consistent mask use in school were associated with SARS-CoV-2 infection, whereas attending school or child care was not associated with receiving positive SARS-CoV-2 test results. | |||||||
| 44 | Australia | Sta | Art | Fi | 10/21/20 | COVID-19 in schools and early childhood education and care services – the Term 3 experience in NSW. Report from National Centre for Immunisation Research and Surveillance (NCIRS). 2020; Published 2020 October. | |
| Three larger outbreaks occurred, all in high school settings. Factors that may have contributed to these outbreaks include attending school while symptomatic, a non–school-related overnight retreat and participation in a music group. All outbreaks were rapidly contained with NSW public health response strategy. The likelihood of cases in educational settings is related to the level of community transmission of SARS-CoV-2. This is consistent with findings from Victoria, Australia4 and from international studies. | |||||||
| 45 | Finland | Epi | School | Art | Ot | 07/30/20 | Transmission of SARS-CoV-2 following exposure in school settings: experience from two Helsinki area exposure incidents. Preprint. MedRxiv |
| When the index was a child, no school transmission was identified, while the occurrence of an adult case led to a 16% AR. Further cases were evidenced in 3 families, but other transmission chains were plausible. It is likely that transmission from children to adults is limited.\ | |||||||
| 46 | Ireland | Sta | Art | Fi | 05/28/20 | No evidence of secondary transmission of COVID-19 from children attending school in Ireland, 2020. Euro Surveill | |
| [E]xamination of all Irish paediatric cases of COVID-19 attending school during the pre-symptomatic and symptomatic periods of infection (n = 3) identified no cases of onward transmission to other children or adults within the school and a variety of other settings. These included music lessons (woodwind instruments) and choir practice, both of which are high-risk activities for transmission. Furthermore, no onward transmission from the three identified adult cases to children was identified. | |||||||
| 47 | Australia | Sta | Art | Fi | 08/03/20 | Transmission of SARS-CoV-2 in Australian educational settings: a prospective cohort study. Lancet Child Adolesc Health. | |
| SARS-CoV-2 transmission rates were low in NSW educational settings during the first COVID-19 epidemic wave, consistent with mild infrequent disease in the 1·8 million child population. With effective case-contact testing and epidemic management strategies and associated small numbers of attendances while infected, children and teachers did not contribute significantly to COVID-19 transmission via attendance in educational settings. | |||||||
| 48 | Italy | Epi | School/ECOC | Art | Fi | 12/2020 | Secondary transmission of COVID-19 in preschool and school settings in northern Italy after their reopening in September 2020: a population-based study. Euro Surveill |
| The overall secondary case attack rate was 3.2%, reaching 6.6% in middle and high schools. More timely isolation and testing of classmates could be effective in reducing virus transmission in this setting. | |||||||
| 49 | Spain | Nar | Let | Fi | 10/05/20 | COVID-19: Social Irresponsibility of Teenagers Towards the Second Wave in Spain. J Epidemiol | |
| This situation is beginning to occur also in other countries, such as Japan. A recent study shows that the majority of young adults who start outbreaks are asymptomatic, when they are not yet aware that they can infect other people, and they do so mainly in situations where they breathe hard and there is little social distance, such as singing in karaoke bars, screaming in pubs, or working out in gyms | |||||||
| 50 | — | Nar | Edi | Fi | 01/26/21 | Data and Policy to Guide Opening Schools Safely to Limit the Spread of SARS-CoV-2 Infection. JAMA. | |
| [T]he preponderance of available evidence from the fall school semester has been reassuring insofar as the type of rapid spread that was frequently observed in congregate living facilities or high-density worksites has not been reported in education settings in schools. | |||||||
| 51 | — | Nar | Art | Fi | 12/11/20 | Summary of Guidance for Public Health Strategies to Address High Levels of Community Transmission of SARS-CoV-2 and Related Deaths, December 2020. MMWR Morb Mortal Wkly Rep. | |
| No single strategy can control the pandemic; rather, a multipronged approach using all available evidence-based strategies at the individual and community levels can break transmission chains and address high levels of community transmission; reduce related illnesses, long-term sequelae, and deaths; and mitigate the pandemic’s economic impact. | |||||||
| 52 | Norway | Epi | School | Art | Fi | 01/2021 | Minimal transmission of SARS-CoV-2 from paediatric COVID-19 cases in primary schools, Norway, August to November 2020 |
| This prospective study shows that transmission of SARS-CoV-2 from children under 14 years of age was minimal in primary schools in Oslo and Viken, the two Norwegian counties with the highest COVID-19 incidence and in which 35% of the Norwegian population resides. | |||||||
| 53 | Switzerland | Sta | Art | Pr | 12/26/20 | Surveillance of acute SARS-CoV-2 infections in school children and point-prevalence during a time of high community transmission in Switzerland. Preprint. MedRxiv | |
| In a setting of high incidence of SARS-CoV-2 infections, unrecognized virus spread within schools was very low. Schools appear to be safe with the protective measures in place (e.g., clearly symptomatic children have to stay at home, prompt contact tracing with individual and class-level quarantine, and structured infection prevention measures in school). | |||||||
| 54 | US, IL | Sta | Art | Fi | 12/30/21 | Data-Driven Reopening of Urban Public Education Through Chicago’s Tracking of COVID-19 School Transmission. J Public Health Manag Pract | |
| By combining local data from a large urban private school system with national and international data on maintaining in-person learning during COVID-19 surges, Chicago believes in-person public education poses a low risk of transmission when the operational burden imposed by the second wave has subsided. | |||||||
| 55 | South Korea | Epi | Fitness Center | Art | Fi | 05/15/20 | Cluster of Coronavirus Disease Associated with Fitness Dance Classes, South Korea. Emerg Infect Dis. 2020 |
| During 24 days in Cheonan, South Korea, 112 persons were infected with severe acute respiratory syndrome coronavirus 2 associated with fitness dance classes at 12 sports facilities. Intense physical exercise in densely populated sports facilities could increase risk for infection. | |||||||
| 56 | South Korea | Epi | Fitness Center | Art | Fi | 08/10/20 | Epidemiological Characteristics of COVID-19 Outbreak at Fitness Centers in Cheonan, Korea. J Korean Med Sci |
| Zumba is an exercise fitness program which combines aerobic exercise with music, and Oriental and Latin dance moves.5 In the fitness centers where the Zumba classes were held, a large number of students had taken classes in a relatively crowded space, although ventilation systems were working properly. … [T]he droplets produced by exhalation or cough of a patient during the exercise have higher chance of reaching the nose, mouth or eye of other class participants directly, as well as remaining on the surface of the exercise equipment and later transmitted by contact. | |||||||
| 57 | US, FL | Epi | School Gym | Art | Fi | 10/16/20 | An Outbreak of COVID-19 Associated with a Recreational Hockey Game — Florida, June 2020. MMWR Morb Mortal Wkly Rep |
| The study was unable to determine exactly where exposure occurred, but hypothesizes it was at the evening hockey game, due to the heavy breathing that occurs, the lack of masks covering the mouth and nose, the transition from ice to bench where players continue heavy breathing or in the locker rooms and lack of other common exposures or time spent together. | |||||||
| 58 | US, FL | Epi | School Gym | Art | Fi | 01/26/21 | SARS-CoV-2 Transmission Associated with High School Wrestling Tournaments — Florida, December 2020–January 2021. MMWR Morb Mortal Wkly Rep |
| An outbreak arising from a Florida high school wrestling tournament in December 2020 had an attack rate of at least 30% (38 of 126 tournament attendees who were tested) and a secondary attack rate of at least 9% (41 of 441 close contacts of the 38 COVID-19 patients) | |||||||
| 59 | US, WA | Epi | Choir Room | Art | Fi | 05/15/20 | High SARS-CoV-2 Attack Rate Following Exposure at a Choir Practice — Skagit County, Washington, March 2020. MMWR Morb Mortal Wkly Rep. |
| Transmission was likely facilitated by close proximity (within 6 feet) during practice and augmented by the act of singing. | |||||||
| 60 | France | Epi | Choir Room | Art | Fi | 12/23/20 | High Rate of SARS-CoV-2 Transmission Due to Choir Practice in France at the Beginning of the COVID-19 Pandemic. J Voice. |
| The characteristics of the viral transmission via close human contacts was probably enhanced by the act of singing, at a phase of intense circulation of SARS-CoV-2 in the population at this period. We report in our study the role of asymptomatic infection carriers initiating a silent chain of transmission of the coronavirus, leading to a cluster under the circumstances of the rehearsal. This study confirms that the transmission of the virus from asymptomatic cases is very efficient. | |||||||
| 61 | — | Agg | Art | Fi | 08/27/20 | Droplets and Aerosols Generated by Singing and the Risk of Coronavirus Disease 2019 for Choirs. Clin Infect Dis. 2020;ciaa1241. Published online ahead of print 2020 Sep 18. doi:10.1093/cid/ciaa | |
| While social distancing is effective in normal social interactions, singing can produce a substantially larger number of respiratory droplets and aerosols than speaking, as it is louder and sustained for longer durations | |||||||
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In the spirit of citizen science and amateur inquiry, I decided to use this search phrase on the Yahoo ( AllTheWeb) search engine.
This NaCap article came up first thing on Yahoo, too. And the next few search return entries were also about these CDC guidances one way or another.
Just another data point . . .
Nice to see our Great Wall in action.
Does Google find it so nice to find their Great Wall exposed in the stark glare of exposure?
The lesson for layfolk seems to be . . . . don’t bother using Google for searching. Use someone else.
For activists, the lesson might be . . . expose this Great Wall over and over and over again, until it smells so bad, even the nose of the public wrinkles up in disgust.
And maybe organize boycotts against certain advertisers for advertising on google, and lift those boycotts if those advertisers stop advertising on google. If it works, do it over and over and over again, until Google has no advertisers left.
Drumlin, your idea of boycotting advertisers on Google will have a better chance of working if they are small, local advertisers where you know, or can talk to their ad buyer, CFO, president, or owners on the phone, face to face, or in email.
The message should be:
“Google is underhanded, unAmerican, betrays the U.S. war dead who died fighting for freedom of expression, and so is your company you if you advertise there. Drop the ads. In one month, if we see your ads on Google media, you go on our citizen shitlist and we will spread the word far and wide about your competitors who do not advertise on Google.”
“By the way, if your service or product is so great, why do you have to advertise it?”
Hmmmm . . . . I don’t know if I want to boycott small local businesses even if they do advertise on google, what with all the pressure small businesses are already under just to survive against the grinding pressure of WalMart, Amazon, etc. I will have to think about that . . . I might rather try it against big and huge businesses which have options other than google, and if they don’t; might well have the money and power to create those options. I am not sure small-to-tiny local-to-hyperlocal businesses can do that.
I may just end up retreating to contributing what little I can to the long range approach of calling attention to how awful a search engine google itself is, to do my small part to encourage steady attrition of the numbers of searchers who even look at google to begin with.
About the subject of the article itself, as a mere layman, I have to wonder whether the CDC has been run by Political Commissars at a level far deeper and far pre-dating anyone Trump might have sent to CDC.
> Political Commissars
The WHO guidance, which I have yet to review in detail, takes the same position on budgetary stakeholders as CDC.
The following search term: cdc school reopening guidance, resulted in a page one hit, 2nd from the bottom on DDG. Adding aerosol, brings it up to the top.
I don’t use Google or Bing, so I can’t test to see how my search results would fare on them.
Hi Milton. Using Swisscows https://swisscows.com, your original search terms brings up Lambert’s article first line on page two, adding aerosols moves it to the top 3 lines on page one — a reprint in Monthly Review, the original, and this repost, in that order. Several lower lines also reference Lambert-originating posts. Swisscows says their searches are based on Bing, and also that they don’t track you. I switched to them from DDG after rumours of DDG being bought out (not true, apparently, or at least not yet) and b/c Swisscows servers are not US based. I know They canfind me if They want me, but 1.) I don’t want to make it easy and 2.) I can’t imagine that they would ever want me for anything. But I’ve been surprised before.
Have you tried Google search console? It appears that if you verify domain ownership you can use it to check index status for individual pages on your site. (I can confirm that it doesn’t appear to be indexed in Google).
Does the mere layman, such as myself, have or even understand Google search console? If not, then we mere layfolk were indeed barred by this google-act of suppressionary interference from finding something that we were searching for. And if so, google achieved what it set out to achieve by suppressing this article well enough that mere layfolk would never ever find it.
Or have they? Between articles like this exposing googelary suppressionism and other means of advising the mere layfolk that non-google search engines exist and can really find things, google may experience a slow silent tide of searcher defections.
You can’t even get to the report unless you verify that you own the domain in question, which makes sense in some ways (if the likes of CalPERS et. al. are indeed trying to suppress NC articles then the information would be most useful to them) but also underlines your point.
The issue isn’t Google search console, as in whether it would make sense for NC site admins to use it to find NC posts. It’s that using Google flushed out a general issue re suppression of our work.
Also happened with our posts on CalPERS and private equity fees. However, for those cases, allies have suggested that CalPERS and perhaps some PE interests have hired “reputation defender” firms to get the posts off the first page. Here there’s no actor, merely Google nefariousness.
I didn’t mean use it to find NC posts. I meant look at what reason they offer for why they aren’t indexing that page, and what remedies they suggest if any. (Know your enemy, and all that).
> Have you tried Google search console?
For obvious reasons, I don’t have a (non-burner) Google account.
What does a burner really mean in this context? If you use Google products sure you can use a different name but they know your IP address and from that all your real info.
I would love anonymity but don’t think it’s possible, would love to be wrong.
> What does a burner really mean in this context?
All correct, but at least I can make them work for the connection amidst a fog of bad data.
Just tried the search term “CDC School Reopening Guidance Suppresses Aerosols Based on Thin Evidence and Driven by Budgetary Concerns” in both Google and DuckDuckGo here in Oz and it was at the top of the results of both. But that may be a result of this article re-appearing once more.
Wouldn’t it be interesting if Google set up another site called Google Classic. It would use the algorithms that they first used when they had finally found their feet and it would be free of all the junk algorithms that they have loaded it with since to do with censorship, de-ranking, etc. that has made it so clunky. I wonder which version of Google people would prefer?
Maybe someone else should go ahead and invent Shinola Search and Social. And see who signs up.
My daughter, with a 1st Grader and being a teacher believes that the lunch room, where children are unmasked, presents the highest risk.
I believe her schools have been open for attendance, I don’t know the actual dates.
She’s in Oklahoma.
> the lunch room, where children are unmasked, presents the highest risk.
This is logical, and the children are also eating close together and chatting. It’s like a restaurant because it is a restaurant.
My view, as a layperson, is that things can be OK if the air is changed often enough to dilute the virus (which you can measure with a CO2 meter as a proxy). And this will vary by the space. Are their windows to open? Can there be fans? How about portable air cleaners? Is the ceiling high or low?
And what about the kitchen? The cafeteria workers need to be safe too, and the kids will contact them when served.
Interestingly, when the Chicago Teachers Union and Chicago Public Schools were engaged in the bargaining process over school re-openings, “ventilation” played a key role in negotiations. Classrooms were required (yes) to have air filters with a full exchange 5 times per hour (so, every 12 minutes). Furthermore, any space where the air could not be replaced every 12 minutes was deemed off-limits – not just to classes but to any activities at all.
I note that the CDC updated its recommendations on “ventilation” a few days ago; cf. https://www.cdc.gov/coronavirus/2019-ncov/community/schools-childcare/ventilation.html
At what CO2 level in parts per million would you deem safe. I recall reading somewhere that any level above 800 ppm is a reason to leave the room.
I don’t recall. Perhaps another reader knows?
Dude, I work deep in the bowels of a very large well-trafficked web site. It is amazing that these damn things work at all.
People do this on Twitter all the time, thinking they’ve been ‘shadowbanned’ or that something is being nefariously suppressed.
There is always a failure rate. Always.
> There is always a failure rate. Always.
Possibly. But going offline and coming back on is… odd. And Google has a track record, not just generally, but with this site in particular.
Something I’ve noted now for several months: NC, in contrast to all other websites I regularly visit, doesn’t come up automatically so I can just press “Enter” after the first 2-3 letters – I have to enter the entire URL every time. This, despite the fact that I visit the site at least twice daily.
Interesting. What browser are you using?
I just searched the post title “CDC School Reopening Guidance Suppresses Aerosols Based on Thin Evidence and Driven by Budgetary Concerns” on Google (using quotation marks, with no reference to the site) and got the original 18 February post as the very first hit. (See this screenshot.)
If I include the site parameter site:nakedcapitalism.com, I also get no hits.
You say it works without site:, fails with? There’s perhaps a 10% likelihood that is an artifact of something about how they index web pages, 90% likely that Google is being a very naughty little person indeed.
3 strikes? Umm what about masks? that would make it 4 strikes.
One almost wonders…
Speaking of opening schools, Newson in California has now made a deal with legislators to re-open the schools for $2 billion in bribes, errr, incentives. This should end well-
https://www.latimes.com/california/story/2021-03-01/newsom-lawmakers-agree-on-plan-to-open-more-california-schools-covid-19
Great work, Sir. Honestly, about the CDC, are you surprised? If the Sainted Fauci said it was raining, wouldn’t you check before getting out your slicker? As to Google, oh well, they’re the wannabe corporatist Pravda now. I still use them for web and email services, but haven’t used their search engine for many moons.
Why is the CDC actively promoting an inferior but expensive and profitable (still on patent) remdesivir and actively suppressing via their tools such as Google cheap and effective early stage Covid-19 treatments ?
Corruption. Institutionalized, pervasive corruption of public bodies. Truly depressing but at least there are notable sources of good information such as this excellent website . Thank you so much, Lambert.
Divadab, try Protonmail for email. I’ve been at it for a few years with no problems. Often people will ask “Protonmail, what’s that?”. Being a public school educator I jump into a few reasons why I don’t use gmail. Eyebrows go up but little thoughts enter the person’s mind and people can change. We don’t “need” google, it’s been thrust upon us from a young age. Students in my classes often say “Duck it!” as opposed to g’it. Such a wonderful sound.
I do still have a gmail account that I check quarterly for friends/people who miss mailed to me. Then again, I make a few comments as to why I’m not in gmail. Modeling is a great behavior without sounding too arrogant.
Regarding Remdesivir, be sure to take your Ivermectin. In India, they’ve been passing it out for free across the country (no small feat) and their average death rate from Covid, over the last few weeks, is about 100 (according to Roy Lab Stats). No I didn’t miss any zeros. “Duck it”. Cheers
First, thank you for this piece! Fyi, I use Duck, but my default is Startpage. They use Google, however, it’s routed through the Netherlands. You can surf anonymously and view sites anonymously. Haven’t used anything else for years. They also sell encrypted email. I got no love for Google…?
(Also, there are companies that are happy to move your name or company info to the 7-8th page on Google so a user gives up and just doesn’t scroll that far. Last time I checked, it was a hefty fee.)
Google will accept money from someone to do that to someone else’s name? This is an active-offense dis-service which Google sells?
Obviously the really important question we should be asking, according to Google, is:
When was school invented?
Lambert, I expect you to have an article on this in the next 24 hours. Perhaps “Ives Smith” can help you with it.
[Edit: Oh crap that’s an assignment]
Just to note that those terms come up first in Qwant too (I find Qwant to be far superior to the non-Google alternatives, at least in Europe).
My conclusion:
Or not odd at all. I’m being pretty circumspect here. Eh?
I think it is both.
Back in the day, torrent links would come up on google search when looking for music. Eventually, those were removed and links to torrents are no longer searchable on google.
I think there is a ‘remove’ algorithm that uses a secret list maintained by humans of non-searchable terms and sites.
When enough smart people figure this out about Google, those smart people will look for other places to do search. Leaving Google searching to the stupid people. Who are the stupid people?
People who keep using Google Search even after knowing about this.
The algorithms seem overly keen in terms of flagging anything as potentially anti-vax, I often take screenshots from news sites and post them to instagram and they routinely get flagged with “since your post includes information about COVID-19, we’ve added a link to a health source” despite containing nothing of the sort.
Lambert S: Google is not a State actor.
Really? When the big tech stacks are effectively the last serious instruments of U.S. hegemony, and Google and NSA might as well be joined at the hip?
> Lambert S: Google is not a State actor
They are ruling class actors, the state and civil society being two aspects of same. That doesn’t imply that Google can arrest you (so far), collect taxes for itself (so far), function as either a legislative, executive, or judicial body (so far). And so on.
Anecdotally, my son’s private K-12 school in suburban Maryland has been open since last fall with zero known covid cases among staff or students. Same at least one other private school that a friend’s kids attend.
Given the amount of false attacks on the CDC, your post may have been caught up in some filter that looks for things like “CDC suppresses” (or repeat uses of the phrase) on the grounds that odds are it’s disinformation. Automated filters of this kind always make some mistakes.
> your post may have been caught up in some filter
That does not give an account of the final act of the play, which is that search worked again. That suggests intervention by some agent.
Yves and Lambert:
The Google aerosol story… Another banner day for you guys. This is why you’re my favorite site.
The only comment I’ll make is on the air turnover rate in schools and other buildings. Sheet metal ducting is cheap, easy to install and meets all U.S. fire and electrical codes. Every U.S. school I’ve ever seen has electricity and either a window or an exterior wall for each occupied room (there may be rare exceptions on this).
So with the usual team of tradesmen, architects and draftsmen I could design and install a code-compliant, properly sized exhaust system that vents to the outside on the exposed ceiling of every classroom at minimal cost in a weekend. Electricity to be provided from the light switch at the door using a low wattage 120 volt exhaust fan and code compliant conduit. This will clearly increase HVAC costs because of the increase in air turnover.
I know a number of middle-aged school teachers who describe local school systems here in the Austin, Texas areas that use phony Covid case numbers, doctored reports on how the cases are treated and threats of firing if the teachers complain to the press in order to make existing classrooms appear on paper to be safe when they are not. At least locally, the teachers are responding to a real, personal health threat when they refuse to work under these circumstances. Here it is not a case of sclerotic unions imposing impossible demands; it is a reasonable response to a real health threat.
And the students? 90% + percent get to public schools in Travis and Bastrop counties via a school bus. This morning I went to the Austin Town Lake YMCA facility to get my morning swim. At the door they have a one-foot-distance thermometer that reads each entrant’s temperature. And they enforce the mask requirements and distancing. There is no reason why every school bus could not have the same system; if your kid is running a temperature, refuses to wear a mask, or is disruptive on the bus, he or she should be denied permission to board. In other words, the system that protects courthouses and courtrooms should be extended to school buses. And if that’s construed by a court as some sort of a Constitutional violation then the Courts should be forced to live with the same rules.
The closure of the schools while my two favorite Austin bars still have live music and dancing is a scandal and frankly the losers are the kids from poor homes where the parents have little money and limited formal education. They are falling further and further behind.
> So with the usual team of tradesmen, architects and draftsmen I could design and install a code-compliant, properly sized exhaust system that vents to the outside on the exposed ceiling of every classroom at minimal cost in a weekend. Electricity to be provided from the light switch at the door using a low wattage 120 volt exhaust fan and code compliant conduit. This will clearly increase HVAC costs because of the increase in air turnover.
Good info. Is there a formula that transforms air turnover into dollar costs? There are starting to be suggested standards for ventilation, like so many air changes per hour, and this might help with the budgetary stakeholders.
The US government is currently meeting with the CEOs of the top tech companies, demanding they “better police” the content they allow. This, according to Constitutional scholars, is a direct violation of the First Amendment, which is de facto censorship. So, the argument these are “private.companies” and thus within their rights to decide what people see no longer applies.
Very interesting article that includes airflow sims of an actual classroom in the NYT. They do sims with windows closed, open, open with an exhaust fan, and exhaust fan plus HEPA filter.
Results are very clear. A room with the windows closed, and the CDC 6 ft spacing becomes a giant petri dish if anyone in there is a spreader. Seems obvious–with no airflow, where are the virions going to go?
https://www.nytimes.com/interactive/2021/02/26/science/reopen-schools-safety-ventilation.html
> with no airflow, where are the virions going to go
The idea is that the big loogies fall to the floor. But since aerosols float, they gradually distribute themselves through the space, like cigarette smoke. Distance is irrelevant. So whenever you see a distance standard, like the famous 6-feet, you are seeing the droplet paradigm in action.
My wife has been a teacher, a curriculum coach, an AP, and a principal at a bunch of public schools in our area. Hard to find someone who knows the reality of the US public school system any better.
The reality is that under normal conditions (say, in 2019), most school districts around here are teetering financially, largely as a result a big unfunded mandates pushed onto schools for which funding has not kept pace. Consequently, staff shortages, supply shortages, decaying facilities, and poor/non-existent maintenance and cleaning are the norm. Many schools have much larger class sizes than the rooms were designed for, and the kids are crammed together. Things are much worse now since teachers are leaving the profession in droves since the pandemic started, correctly deciding that a modestly paid, brutish and low-prestige job is not worth dying for.
When my wife hears prospective plans about everyone in the school wearing masks, keeping 6 ft apart, and all surfaces being meticulously cleaned, she can’t restrain her laughter. “Who is supposed to be doing all this, and who will be paying for it?” she wonders.
The CDC recommendations described above are pretty much fantasy even leaving the aerosol issue out of it.
> When my wife hears prospective plans about everyone in the school wearing masks, keeping 6 ft apart, and all surfaces being meticulously cleaned, she can’t restrain her laughter. “Who is supposed to be doing all this, and who will be paying for it?” she wonders.
We seem to be destroying both the notion of public health and the notion of public education. Thanks, neoliberalism!
In the kingdom of the brainless, the half-brained man is king.
In the kingdom of the witless, the half-wit man is king.
The math of CO2 related to ventilation is simple. If ambient (outdoors) CO2@ is 400 ppm, then at 800 ppm indoors 1% of the air you breathe has been used by some else. At 4400 ppm 10% has been used.
If you have a CO2@ meter, try to keep your environment below 700 ppm for safety per Jimenez et al. Be concerned at 800 ppm and go elsewhere above that.
PS A good CO2 meter can be had for $100 – 200. It is well worth the investment since masking does little and and social distancing does nothing for aerosol transmission.
> A good CO2 meter can be had for $100 – 200. It is well worth the investment. .. Try to keep your environment below 700 ppm
Thanks for this. I do not believe you are correct that masking “does little” against aerosols; see e.g. here and here. (Of course, the mask itself matters, as does the manner of wearing it — for example, it shouldn’t be open at the sides.)