Pfizer presents data ahead of recommendation of EUA for kids.

Earlier today, the CDC's Advisory Committee on Immunization Practices met to make their recommendation about Pfizer's EUA for kids 12-15. This means that Pfizer presented their data, and that data was made available online. The data is not as detailed as what we've been getting for the FDA's meetings, but it's still a lot.

The trial involved about 2000 kids, divided equally between vaccine and placebo. Counting 7 days after the second shot, a total of 18 kids got covid, all in the placebo group, for an efficacy of 100%. Interestingly two of the 18 had antibodies from a prior infection, so they were on at least their second round of covid. Counting immediately after the first shot, there were 3 cases of covid in the vaccine group and 35 in the placebo group, for an efficacy of 91% from day one.

The 12-15 age group had 1.7x higher antibody levels than did the 16-25 age group.

Most kids had a sore arm after vaccination, and 11% had flu-like symptoms severe enough to disrupt normal activities. A few had swollen/painful lymph nodes. No anaphylaxis and no Bell's palsy, but we wouldn't expect those with only 1000 vaccinees.

Serious adverse events included:

• 1 case of abdominal pain (vaccine group)
• 2 cases of appendicitis (both in placebo group)
• 1 case of neuralgia (vaccine group)
• 4 psychiatric disorders (all in vaccine group)

They also presented some data about covid in kids. Given the increased infectivity of the variants, anyone who isn't vaccinated has a very high risk of eventually getting infected, especially if you live in a place with a low overall rate of vaccination. About 20% of those aged 5-17 have already been infected, which leaves the rest vulnerable to infection.

Something that I didn't know was that even though flu is more likely than covid to lead to hospitalization, covid is lasting much longer than flu. That means that more kids are getting covid than usually get flu, which means that the cumulative number of kids hospitalized for covid is a lot more than the number typically hospitalized for flu. (graph below)

Another important observation is that the majority of kids hospitalized for covid had at least one comorbidity. So it looks like a kid with something like asthma or diabetes is at much higher risk from covid, and therefore has more to gain from vaccination. The graph below has a full list of comorbidities in hospitalized children.

Covid deaths in this age group are very rare. The next graph shows that infants are actually the highest-risk group amongst children. They do happen, though, and vaccination would almost certainly have prevented those deaths.

A total of 3700 MIS-C cases have been recorded in the US so far. This is an inflammatory condition that happens in kids (and some young adults) after covid. The majority are admitted to intensive care and 1-2% die. These numbers are actually a lot lower than I initially feared. Given that something like 15 million US kids have gotten covid so far, MIS-C is still pretty rare. But again, vaccination would probably have prevented all of those serious illnesses and deaths. If you add together covid deaths and MIS-C deaths, the pediatric death toll is about 300 in the US.

They also pointed out that kids can spread covid. I'm not going to belabor this because I've written about it before. Being vaccinated would probably mean a reduced risk that they would spread it to someone with a much higher risk of serious illness or death.

So that's my summary what we have from today's meeting.

I also did a search of VAERS for deaths in 16 and 17 year olds who had gotten the Pfizer vaccine. There were three, out of 2.2 million shots given to this age range. One was a 16 year old girl who had been born with spina bifida. She had a tube draining excess cerebrospinal fluid from her brain into her abdomen, and required a urinary catheter. The autopsy revealed multiple bacterial infections, including in her cerebrospinal fluid and bloodstream. So that's not something that could be blamed on the vaccine. Probably the tubes led to the introduction/spread of the bacteria.

Another was a sudden cardiac death in a 16 year old girl. There was a note that she was on oral contraceptives, which might have lead to a blood clot, but at least from the VAERS record it's not definitive that it was a clotting problem. The third was a suicide in a 17 year old boy. I think it's worth mentioning that immune activation can cause low mood, especially in light of the three cases of depression in the vaccine group in the trial. The most common theory for why is that if you are sick, your body wants you to curl up in bed and conserve your energy until the infection passes. There isn't enough data here to say that the vaccine caused the depression, but it's at least possible.

So it might not be a bad idea to explain the biological basis of depression to your kids and that there is a small possibility that the vaccine might make their brain do some weird stuff, but that it isn't permanent. The immune reaction takes about a month to do its thing and go back to the resting state.

Covid risks: https://www.cdc.gov/vaccines/acip/meetings/downloads/slides-2021-05-12/04-COVID-Oliver-508.pdf

Pfizer's presentation: https://www.cdc.gov/vaccines/acip/meetings/downloads/slides-2021-05-12/02-COVID-Perez-508.pdf

CDC presentation: https://www.cdc.gov/vaccines/acip/meetings/downloads/slides-2021-05-12/03-COVID-Wallace-508.pdf