Natural (infection) vs vaccine immunity in young children

[M_T]

EDIT: The CDC report referenced above is here

Welcome, NGC.   I remember you making available some information about your school's policy.  I spent a decade in Austin and have a best friend with a 10yo grandchild there, and a brother who is a physician.  I generally try to keep up with what is going on there, but not as closely as where I live.

Did you see this posting of links to the documents presented by & to the FDA about the Pfizer vaccine for 5-11 year olds?


I think most people will agree that the situation with regards to children is complex.  There are both short-term and long-term potential effects to the children and their caregivers (and then those they interact with). Effects of the vaccine on this age group are being estimated from effects on another age group.  The level of community infection over the next few months or years is unknown.

While the model isn't explained enough (IMO), the FDA did models of the benefits & risks (BR) of vaccines on children under various scenarios.  As models typically go, everything is an estimate based on some data that isn't perfect.  The FDA authors felt their estimate of excess myocarditis rate was high, but used it anyway as that was the data they had.

IMPORTANTLY, it appears that the numbers shown are only for the age group indicated (say, 5-11 yo males).  It does not show reductions in cases (and thus hospitalizations, cases of myocarditis, and deaths) for the total (all ages) US population if the 5-11 age group is vaccinated.  It only shows Benefits vs Risks among the 5-11 age group.

The BR presentation lists its major limitations as

• Model assumption about constant incidence rate generates great uncertainty on the estimate of benefits
  
• Vaccine efficacy may change due to new emerging variants of virus
  
• Hospitalizations and ICU stays from COVID-19 and myocarditis are not equivalent and cannot directly compared
  
• The benefit of reducing COVID related multisystem inflammatory syndrome in children may not be fully captured by preventable hospitalizations, ICU stays and deaths due to COVID-19
  
• This BR risk assessment does not consider potential long-term adverse effects due to either COVID-19 or myocarditis
  
• This BR assessment does not include secondary benefits (reducing COVID-19 disease transmission) and risks
  

Among the scenarios run, the only one that showed excess risks vs benefits was one in which COVID cases in the community dropped by 90% (basically from the high levels of Sep. to the lows of June).  Even then, the authors felt that the benefits might outweigh the effects when the uncertainties were factored in.

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Opinions:

If I were to update the outlook over the last two weeks, it appears to me that vaccine effectiveness for the general population is dropping faster than expected, and that cases appear to be leveling off (deaths lag cases by 3 weeks or so) after dropping from the peak in early September.


If you look at the graph of infectons in the US
 
the number of infections begin to take off in the Aug-Sep time frames of both 2020 and 2021.  Think of that in relation to school starting.  However, interpreting the temporal patterns of infection is difficult because an unknown number of infections aren't reported, making it difficult to see when regions have relatively few people likely to get infected.  The number of repeat infections simply isn't available.  Note that the ratio of true infections to reported infections may be different from Dec. 2020 to Sep 2021.

The US tried voluntary vaccinations, but the failure of that plan shows in Sep. 2021.
The US has seemingly now taken a stance differently than I think it did for diphtheria, polio, and smallpox.  It is only indirectly forcing people to get vaccinations by having institutions (schools, companies) require them.  This leads to dilemmas when a school is asked to make an exemption.  If one exemption is made, why isn't everyone exempted?   Doctors, like the general population, have a wide range of opinions.  I'm sure there is at least one physician in the area that believes no child should be vaccinated and another physician that believes all children should be vaccinated.  (There was a farce in California that you could get marijuana with a prescription.  You can imagine how hard that was to find.)

From an individual's perspective, the safest & easiest course is if everyone else in their universe becomes immune without the individual getting the vaccination.   Clearly that doesn't work if large segments of the population choose that course.  

I guess if I were a small school, I would find an independent physician to evaluate requests for exemptions.   While most physicians hesitate to disagree with another physician (and so would tend to rubber stamp exemptions), having such a gate-keeper would be defensible and somewhat consistent. A lay-person overruling a MD wouldn't work well.  If the lay-person or MD disallows an exemption, there will be a dispute.  If the lay-person or MD allows an exemption, there may be a dispute from those that got the vaccine.

Remember that you have to set very clear guidelines and those guidelines have to be effectively and continually communicated.  (I don't know if you saw the post on the Cal football team.  One of the issues is that team members were thinking of rules from the July time frame (when cases were low) that had been changed in August when the first signs of vaccine effectiveness drop was seen by the CDC.  So the coach is claiming that the team followed the rules, but the Health Officer is saying otherwise.)