Because England has excellent population data on #COVID19, we can make pretty accurate estimates of risk to children 🧵
Fortunately, these risks are extremely low
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Note when possible that we want to know rates *per infection*, not per positive test
This is because tests are contingent on how much you test, which is different across time and places
Risks per infection are much less changeable, and what we really care about
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Let's take the first 12 months of the pandemic up until Feb 28th 2021
Estimates based on seroprevalence are around 25% children <18 were infected by this point (16+ was >30%, younger will be a bit lower)
There are 12mil children in England, so this is 3mil infections
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By that point there were 5000 admissions <18
We know from ISARIC data at least 20% of these were incidental positive tests, so max 4000 admissions due to COVID-19
That's a hospitalisation : infection ratio of 1 :750
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By that time there were 61 deaths with a positive test
Of these, only 25 were caused by COVID-19
That's a death : infection ratio of 1 : 120,000
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As there is no definition for "long covid" in children, the best we can do is estimate relative risk from the CLoCK study of having 3 or more symptoms 12w after a COVID-19 test
30% if tested positive, 16% if tested negative
RR=1.8 if positive for SARS-CoV-2
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Approximate risks to children from SARS-CoV-2 infection summary:
Hospitalisation: 1 in 750
Death: 1 in 120,000
Test +ve for SARS-CoV-2, symptoms at 12w RR=1.8
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Vinay points correctly to the bias prone endpoint of self reported URTI symptoms and implies the entire difference between groups could be due to “the placebo effect”
The problem is, this is almost
certainly not a result of placebo
It’s detection or ascertainment bias
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Vinay describes as much in his piece, when he mentions different interpretations of vague symptoms between people with or without masks depending on their beliefs
Wear a mask and wake up tired? Probably nothing
Not been wearing a mask? Could be the start of something…
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The rationale behind this is that some have postulated PASC could be due to viral persistence - SARS-CoV-2 hanging around when it should have been cleared
Anti-virals might help clear the virus and resolve symptoms
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The evidence base behind this theory is far from clear, but given the general mess of evidence in the field this seemed like a reasonable trial
It could also serve as possible therapeutic diagnosis (if it works, it gives evidence towards the possible cause)
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