School System Outbreaks of Covid
Blogger and Commenter RJS
Briefly: even though US Covid infections have been falling since labor day, there’s been anecdotal evidence it’s rising among school age kids . . . at the same time, there are now solid studies showing that the mRNA vaccines administered in the US are losing their effectiveness . . . hence, it looks likely that about the time the holidays roll around, many of those infected kids will be mingling with their vaccinated grandparents, who may no longer be protected against a serious case . . . no doubt the CDC sees that too, hence their sudden urgency to push booster vaccinations…
The drop in new US cases is mostly a story of the South, where the August surge was most pronounced, and to a lesser extent to the West, and that in turn was due to the turnaround in the high population states like Florida and Texas that led the surge . . . the seven day average of new cases in Florida, for instance has fallen from a 21,693 daily at the end of August to 5,875 yesterday; that drop alone is enough to take 10% off the national average . . . meanwhile, new cases in the Midwest and Northeast remain near their peak . . . I don’t know what’s going on in most of those states, but i have a few articles that might give us a clue:
Pennsylvania COVID-19 cases and deaths up tenfold after full reopening of schools –Coronavirus cases and deaths are once again surging in Pennsylvania, with the seven-day average of daily new cases now standing at 4,774, a jump of over 30 percent in the past 14 days and tenfold since August. The number of deaths is also up tenfold in less than two months, climbing from a seven-day average of four per day on August 1 to 42 per day at present. The surge in infections and deaths has been driven by the lifting of all restrictions and the reopening of schools in August,
Coronavirus data for Friday, Sept. 24: Teens account for largest COVID case increase in Michigan – – Michigan’s daily COVID-19 case rates have been climbing for 2.5 months, including a nearly 50% increase over the last two weeks. Children 10 to 19 years old represent the largest week-over-week increase in cases (27%), as well as the highest average daily case rate per capita (386.7 cases per million people). That’s likely due in part to the return to school in recent weeks, which resulted in an increase in school-related COVID outbreaks.
If the current Covid surge is mostly in the schools, then what’s happened in Israel might provide a warning for us: from Science.org Sept 21st:
Israel’s struggles to contain COVID-19 may be a warning for other nations. Widespread boosters don’t dent case rate as schools, holidays foster spread – Israel, among the first countries to launch coronavirus vaccinations and the first to roll out booster shots on a large scale, is offering a disturbing glimpse of what could be in store for other rich nations if they begin to give boosters this fall. Israel launched its pioneering booster campaign in late July, prompted by a surge in cases reflecting the extreme contagiousness of the Delta variant, the loosening of restrictions, and an apparent waning of protection from vaccines given in early winter. But cases have risen even higher since, suggesting boosters are far from a panacea when children and others remain unvaccinated. Since 30 July, Israel has given a third shot of messenger RNA vaccine to more than 3 million people, including a majority of those 40 and older. Yet Israel is “stuck in a status quo of 1000 or 900 new cases per million per day,”
Even though Israel’s new infections are down by a third from the peak, their new cases per capita are still close to the highest in the world, with only Serbia, Cuba and the UK in the same range among other countries with sizable populations, and that’s despite almost a third of Israel’s population having received three shots . . . and that’s also despite an R0 number that’s fallen slightly below 1 . . . so what’s going on there? as the Science article explains:
The paradox reflects social realities, Sharon Alroy-Preis, director of public health services for Israel’s Ministry of Health, told the meeting. Public schools opened on 1 September and the Jewish High Holy Days, with their attendant travel and family gatherings, stretch from 6 to 27 September.
“The combination of [unvaccinated] children meeting in school followed up by large family gatherings is the recipe for mass dissemination of the disease,”
What has happened in Israel suggests that we might also be setting ourselves up for a similar surge come the holidays when the generations mingle, should the widespread infection rates continue in the school systems, vaccines not withstanding . . . that potential for a holiday surge in the US is further exacerbated because most of the vaccines that we’ve already administered are losing their effectiveness . . . 57% of the vaccines administered in the US were Pfizer, and the effectiveness of Pfizer vaccines starts to wane after 4 months:
Pfizer Vaccine Protection Wanes, C.D.C. Study Shows – The New York Times – The Centers for Disease Control and Prevention released data on Friday indicating that the level of protection against Covid hospitalizations afforded by the Pfizer-BioNTech vaccine dropped significantly in the four months after full inoculation. The new study found that from two weeks after recipients got their second dose — a point at which they are normally considered fully vaccinated — to four months later, the Pfizer vaccine was 91 percent effective in preventing hospitalization. Beyond 120 days, though, its effectiveness fell to 77 percent.
The Moderna vaccine also wanes over time, but not as quickly:
Moderna’s COVID-19 Vaccine Protection Drops by 36% After 12 Months – In a new study published on Sept. 15 to a preprint server—the study is not yet peer-reviewed — researchers at Moderna .. report that people vaccinated within the last eight months had 36% fewer breakthrough infections than those who were vaccinated a year ago. That suggests vaccine-induced immunity is likely highest shortly after people get their recommended two doses of the vaccine, and starts to drop afterward.
And the loss of protection for those who are vaccinated is worse for older people:
Vaccine protection against Covid-19 wanes over time, especially for older people, CDC says – — The protection provided by Covid-19 vaccines appears to wane over time, especially for people 65 and older, a US Centers for Disease Control and Prevention expert said Wednesday. Effectiveness started to wane a few months after people were fully vaccinated — defined as two weeks after their second dose of either vaccine.
“For individuals 65 plus, we saw significant declines in VE (vaccine effectiveness) against infection during Delta for the mRNA products,”
The US vaccination rate peaked in mid April and the vast majority of our vaccines were administered by the end of May, and by July, vaccine uptake by Americans had slowed to a trickle . . . hence, most of those who received the Pfizer vaccine are at increasing risk of contracting a more severe form of Covid than we’ve come to expect in the so-called “breakthrough” cases, and those who got the Moderna vaccine won’t be far behind . . . my calendar shows that that Thanksgiving is now less than two months away . . . while Israel might be able to administer 3rd doses of the Pfizer vaccine to a third of their population in 2 months, there’s almost no chance that the US could pull off the same…
note that this post started as a pair of comments on the NDD post titled Coronavirus dashboard for September 22: the Delta wave rolls out? here at Angry Bear and was subsequently composed into a longer bulletin for my mailing lists, and then later edited down to what you see above for this post here today; hence, some of the commentary is dated, specifically “new cases in the Midwest and Northeast remain near their peak” is no longer true, they have also turned lower, and the reference to “yesterday’s” Florida stats refers to Wednesday of this week..
here are a few more anecdotal articles included in my original bulletin to make my point about a school system outbreak in this part of the country:
this is from over a week ago
last week i had this article for Ohio, now reflecting Ohio data from three weeks ago, when Ohio infections were at their peak:
Interesting to watch the data but in Wisconsin we heard the same warnings last Thanksgiving and Christmas before there were any vaccines and the numbers not only did not push up it is pretty clear they continued down after Thanksgiving and kind of plateaued at a relatively low level post-Christmas (when vaccinations had just started, to be accurate). I’d guess that there are some space, time and prior infection effects that are still not well understood that are important to case level trajectories.
Thanks. That looks like Wisconsin last fall. My gut was that the least socially distanced part of the population built up immunity and achieved a kind of herd immunity that caused a big drop, while another sort of “pace of infection” kind of burbled along among the socially quieter groups. Think, in particular, college age kids and their close associates. But I can’t say I worked lots of data to support that.
The Rest of it
Maybe these surges have some kind of time function where a given geography – even sort of arbitrary like the outlines of a state – will experience a ramp up and then down in a given period. Maybe that late September 2021 is the peak point of the “July” surge. I do not see that behavior really explains much about these trajectories. I’m pretty sure that in 2020 it was not that at least this part of Wisconsin (northeast) in November suddenly took masking to a new level and restricted their social interactions in any important ways. Public schools were already mostly closed as the infections ramped up and no big school districts suddenly went virtual in November to short-circuit infections. It felt much more like the reaction simply struggled to find more reactants and died back.
last year’s experience doesn’t apply much, if at all, to this years, first, as you note, most school districts were already shut down or virtual last year, but this year almost all are open and in person, except for the handful where the outbreaks are so bad that a majority of student are quarantining, and secondly because last year’s Covid strains weren’t infecting the young much, but this year Delta seems to be going right to them…
looking at Wisconsin’s infection history, it appears your cases peaked at around 6900 per day last November, and fell to around 2200 a day after Christmas…that experience is an outlier to what was happening in the rest of the country, where cases began rising from around 45,000 a day in early October almost continuously until they peaked around a quarter million a day in mid-January…
at any rate, my point here was not to forecast an outbreak around the holidays, or anything like that; i have no crystal ball; this post is just a series of observations of the current state of play, tied together with statements that typically start with “if” or “might” and lead to statements that begin with “could’…hopefully someone with more smarts than i will figure a way to head of the potentials i’ve outlined & make my post moot by the time Thanksgiving gets here…
based on the latest figures i have, it appears that nearly a quarter of our new cases have been children: