🇨🇦Ontario reporting the highest rate of post vaccination myocarditis I've seen:
1/1287 (777/mill) in males 18-24 if they received Pfizer then Moderna within 30 days
Moderna >6x higher risk of myo than pfizer
This & the new study from France discussed 🧵
In Ontario, the post Pfizer myocarditis rate has been higher in 12-17 yos than 18-24 yos. Given Moderna has >6x higher risk of myo in Ontario, why would we in the US & approve Moderna for adolescents?🤔
& is @cdc really calling 1/1287 rare? 🤨
Pfizer-Moderna was also the combination that had the highest rate in the Nordic countries

Interestingly in the Nordic study, where countries have different dose interval policies, there was no clear correlation between dosing interval & myocarditis rates

🇫🇷 The French study just released also shows higher rates of myocarditis in males after moderna, including males over 30. The French study only included hospitalized patients. Ontario data had 30% who weren't hospitalized.
This graph from the French hospital study shows myo and pericarditis rates/100,000 by age
moderna (🔵)
pfizer (🔴)
Note the y axis is different for females and they are at lower risk than males but not at no risk; moderna riskier for females, too
The French study also shows a clear correlation between history of myocarditis pre-vaccine to development of myocarditis again post-vaccine & this history should be taken into consideration in vaccine recommendations.
Finally, remember retrospective studies are not as reliable as prospective and in a prospective study, Hong Kong reported a 1/2700 risk of myocarditis after dose 2 in 12-17 year old males and we can only expect this to be higher (maybe 6x?) with Moderna
I think it would help restore some trust if the @cdc would acknowledge the above numbers in their guidelines & weigh vaccination risks with current covid risks by age, sex & health status
They should also make clear there is increased risk of myocarditis after Moderna.
The link to the French study did not work, so here it is: nature.com/articles/s4146…
Finally, when @KrugAlli @ifihadastick & I published our analysis in February data didn't support vaccinating already infected boys who weren't high risk w/even 1 dose pfizer given myo risk so why would we now recommend 2 moderna for them? Boggles the mind

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More from @TracyBethHoeg

Jun 22
I'd been looking forward to meeting Senator Pan. I think we both want the best for kids
Not sure "minimizer" applies to someone dedicated to learning the data & considering tradeoffs of continued testing. My take: we should follow Scandinavia's lead & drop school covid testing🧵
Here's my testimony (Part I) which I would love to discuss in detail w/Sen Pan & others (over coffee or a beer!) so we can work together to develop sensible policies for kids, who the data would suggest are lower risk from covid than he suggests. See👇
Read 11 tweets
Jun 18
Agree @KelleyKga this @CDCgov figure is totally misleading

1) it compares cumulative covid deaths in kids over 26 months to annual numbers from other conditions (!)

2) doesn't separate out deaths w/vs from covid

(Remember Finland had 0 peds deaths from covid as of March 2022!) Image
Here you can see form the source preprint, that even without separating out with vs from,
annually COVID-19 is the 9th leading cause of death in children
medrxiv.org/content/10.110… Image
But beyond that, here @KelleyKga explains why the study using CDC’s NCHS is problematic. Here deaths are attributed to covid & given the ICD-10 U07.1 code if Covid is listed *anywhere* on the death certificate even when there are multiple caues of death
Read 7 tweets
Jun 13
Looking at these 2 studies, I wonder what *good* evidence we have to suggest vax provides sig addt'l benefit to those who have nat immunity

L:"hybrid" vs "natural" immunity against infection
R: "h" vs "n" against hospitalization cdc.gov/mmwr/volumes/7… ImageImage
By "good" evidence, I mean from studies not confounded by unvaccinated populations having higher rates of risk factors for sympt/severe disease.

Credit goes to @PeterAttiaMD for the above fig on the right. He used the data from the MMWR pub to make the figure.
These studies were done at a population level and, it needs to be said that specific demographic groups may indeed benefit from vax after infection. It's just we don't consistently see clear benefit of "hybrid" over "natural" immunity at a population level.
Read 5 tweets
Jun 8
👇16-17 yo boosters. Clear myo risk & for what benefit?😕
-Estimates for males 12-17 dose 2 likely underestimates (up to 360/million per some studies) & now boosting may have higher risk
-Consistent w/Nordic data: no obvious decrease in myocarditis risk w/spacing of doses🧵
A summary of international rates of adolescent myo/pericarditis after dose 1 and dose 2 from my study w/@KrugAlli & @ifihadastick
Shown here from Nordic @JAMACardio study: no obvious differences in myo rates in 16-24 year old males w/different dose interval policies (suppl 3 Fig 2)
Dose 1 to 2 intervals by Nordic Country:
🇩🇰DK 3-4 weeks
🇸🇪SE 4-8 weels
🇳🇴NO 8 weeks
🇫🇮FI 10-12 weeks
Read 5 tweets
Jun 6
Excellent article by @DrJBhattacharya. @ashishkjha spread fearmongering misinformation by @jeremyfaust which clearly overestimated child covid deaths & underestimated flu deaths -obvious by just looking at the CDC's own data!
Dr. Jha, please apologize.
Another nice summary of what went wrong with Faust's analysis:
Just looking here at the estimated flu burden quickly shows that @jeremyfaust 's numbers were misleading in terms of underestimating influenza deaths.

Read 8 tweets
May 14
This new JAMA study is worth discussing. It found that, this winter, vax effectiveness in 12-15 yos dropped to 0% after 3-5 months & vaccinated were MORE likely to test+ at month 7. May be confounded (see🧵)
But I don't see this as good reason for boosters
jamanetwork.com/journals/jama/… Image
I think the most likely confounder here which could lead to the calculated negative effectiveness is higher amount of immunity from prior infection in the unvaccinated group. It could also be related to different behaviors in the two groups. Need randomization to sort this out
Remember, we have seen the same pattern of negative effectiveness in 5-11 year olds in NY so I don't think what we are seeing in the JAMA study is limited to 12-17 year olds
Also, remember, this is only looking at infection rate and not severe disease rate Image
Read 6 tweets

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