Thread by @DrEricDing

Worrisome—UK 🇬🇧 data shows suddenly higher #COVID19 positivity % in England 🏴󠁧󠁢󠁥󠁮󠁧󠁿 (where #B117 highly dominant) in children ages 5-9, in both boys and girls, sustained each week over 4 consecutive weeks. Ages 0-4 positivity also increasing. Israel 🇮🇱 has also seen kids case trend.

2) As noted by @dgurdasani1, this is all despite these data really underestimating infection in children (as they are based on symptom based testing). And positivity rates appear highest in early year settings (fully open) & primary schools (20% attendance).

3) Dr @dgurdasani1 believe it is related to schools in England 🏴󠁧󠁢󠁥󠁮󠁧󠁿.

https://twitter.com/dgurdasani1/status/1360184562672955395

4) Cases are dropping because of general lockdown restrictions across UK, but the notably higher positivity in children 5-9 especially stands out—kids positivity didn’t used to stand out last year at all.

5) Israel 🇮🇱 is seeing a sharp rise in the number of children and teens getting #COVID19, where #B117 rising.

>50,000 children have been diagnosed with #COVID19 since start of Jan, many more than Israel saw in any month during the first or second waves.
m.jpost.com/health-science…

6) “We got a letter from the Israeli Association of Pediatrics that says they are very worried about the rate of disease in younger students,” Health Minister Yuli Edelstein told The Jerusalem Post. “This is something we did not witness in previous waves of corona.”

7) Instead of around 29% of new cases coming from children and teens, as in the second wave, now they are around 40% of cases, Public Health Services head Sharon Alroy-Preis said in the Knesset on Monday. The greatest spike was in children between ages of **6 and 9** (matches 🇬🇧)

8) “according to Cyrille Cohen, head of Bar-Ilan University’s immunotherapy laboratory, the numbers seem to be rising. one hypothesis is that it is tied to the British 🇬🇧 mutation #B117, which has spread rapidly across Israel.”

9) “The British variant is more contagious, so it increases the chances of infection in children,” Cohen told the Post.”

10) I’ve alluded to this trend in kids 0-9 before over a month ago in the #B117 data... while kids overall lower risk than adults, #B117 has yielded greater increase in attack rate in kids 0-9 than in those over age 10, compared to the older common strain.

https://twitter.com/drericding/status/1347745279320186880

11) I’ll also leave this Italy 🇮🇹 village outbreak story here.

https://twitter.com/drericding/status/1357599530296958982

12) Dr @dgurdasani1 thinks it’s likely schools.... she points out that in the initial lockdown, kids positivity dropped the same as adults, but then diverged from adults because of gradual school reopenings. It’s a good point.

https://twitter.com/dgurdasani1/status/1360184561334902784

13) On the bright side, lockdowns do work. Can we sustain the case drop once all schools are reopen is the question. Maybe we can afford some small school related transmission while keeping overall transmission low enough while aiming for general suppression. 🤔

14) Here are the school attendance rates in the UK. The sharp parallel drop of kids & adults occurred during the winter break. But once schools reopened, then the positivity started diverging between kids and adults. We can’t delude ourselves.

15) Notably absent from new CDC guidance was ventilation. In one short paragraph, CDC suggested schools open windows & doors to increase circulation, but said they should not be “if doing so poses a safety risk or a health risk.” #COVID19 nytimes.com/2021/02/12/hea…

16) This 🧵 makes the clear case that school transmission of #COVID19 does occur, & increases when cases levels rise—which then further drives school transmission. It’s a deep analytical 🧵 but that’s the Bottomline. Schools are not impervious to risk.

https://twitter.com/sarahdrasmussen/status/1356302433237008391