Thread by @HelenBranswell

1. #ACIP, @CDCgov's vaccine advisory group, is meeting today to discuss Covid boosters. I'll be live tweeting.
I don't believe there are going to be any votes today, so no changes in current policy. This meeting will shed light, though, on how the committee sees 4th doses.

2. If there are no votes at today's #ACIP meeting, that will mean the current US position on 4th doses — people 50 and older & people who are immunocompromised "may" get a 4th dose if they wish — will remain in place. It will not transition to a "should" recommendation.

3. @CDCgov's Ruth Link Gelles is racing through a presentation on vaccine effectiveness. I'm not going to be able to tweet all of this. Too fast. Her slides are here.
cdc.gov/vaccines/acip/…

4. The gist of her presentation: vaccine effectiveness for the mRNA vaccines was better after 3 doses than 2. The 3rd dose seemed to limit waning of protection. This is in immune-competent people. Immunocompromised people still don't get great protection, even with 3 doses.

5. So much for mix-and-match. Nicola Klein, from Kaiser-Permanente, is presenting now. She reports most people who got boosters were boosted with the same vaccine they received as their primary series. #ACIP

6. Klein says Kaiser Permanente Northern California has been looking for myocarditis & pericarditis in people who received a Covid booster. They've found 139 confirmed cases so far.

7. Though there are some cases of myocarditis and pericarditis after dose 3, the rate of such cases is lower than after dose 2. #ACIP

8. This is interesting: After dose 3, the risk of myocarditis & pericarditis varies by age group. In people 12 to 39 yo, the cases were mostly myocarditis & onset was within a week. For people over 40, pericarditis was more common & onset was not as immediate. #ACIP

9. (repeating to fix numbering)
@CDCgov's Tom Shimabukuro is presenting now on side effects reported after Pfizer and Moderna vaccines. Side effects after dose 3 were generally less common than after dose 2.
(I must be an outlier. Dose 3 was a doozy for me.)
#ACIP

10. #ACIP member Camille Kotton asked if there are data showing whether the Moderna booster (which contains half the antigen of doses 1 & 2) led to lower rates of reactions. The short answer is no.

11. Interesting but out-of-date data on the percentage of Americans with antibodies that suggest they've had Covid infection. (They test for a part of the virus that isn't targeted by the vaccine, so they can distinguish between vaccine antibodies & infection antibodies.)
#ACIP

12. @CDCgov's Sara Oliver is presenting some interesting data right now. CDC use data from Israel's 4th dose program to calculate benefits in the US from giving everyone 50 and older a 4th dose here. The benefits are not very large. #ACIP

13. Oliver reports that the @CDCgov analysis shows the bang for buck reduces with each dose. #ACIP

14. Anyone interested in going over the slide presentations from today's #ACIP meeting can find them here: cdc.gov/vaccines/acip/…

15. A recent @statnews survey on people's intentions re: boosters was just cited at #ACIP!

16. Oliver says about 4.3M people 50 and older have received a 4th dose of Covid vaccine (2nd booster). #ACIP

17. Oliver says #ACIP's Covid vaccines work group supports the current recommendation, ie that people 50 & older & immunocompromised people should be allowed to get a 2nd booster if they wish.
This means the WG is not advocating changing the recommendation to urge 2nd boosters.

18. An important thing to note here is that for immunocompromised people, the 2nd booster will be a 5th shot. That's because last summer #ACIP & CDC recommended that for people who are immunocompromised, the primary series should be 3 doses, not 2.

19. Repeating to correct an error in previous (deleted) tweet 19.
Immunocompromised people can get a 5th dose four months after their last dose. Oliver said that that means the first eligible people in this group will be able to get their 5th dose in mid-May. #ACIP

20. So who might want to get a 2nd booster now? According to @CDCgov, they could include people with underlying medical conditions, who live with someone who is immunocompromised or who themselves are immunocompromised. #ACIP

21. Who might consider waiting for a 2nd booster? People who have recently had Covid, and people who want to wait. @CDCgov staff are suggesting getting a booster in the fall may be important and people may want to wait until then. #ACIP

22. #ACIP member Veronica McNally asks about people who believe they were infected but didn't get a test. @CDCgov's Elisha Hall says the guidance suggests people can time their 2nd booster from 3 months after a positive test or the onset of symptoms.

23. #ACIP member Pablo Sanchez asks a very sensible question: Why would people who've been vaccinated and also infected with Covid need a 2nd booster? A @CDCgov staffer says anyone who was recently infected — with Omicron — is probably protected against Omicron.

24. #ACIP is half way through a 30 minute public comment period right now. The speakers are drawn by lottery, but today's roster is almost single minded: Authorize Covid vaccines for children under 5 now!
The frustration is palpable. A mother of an 8 month old is now in tears.

25. There won't be satisfaction for these parents today, unfortunately. #ACIP cannot move on Covid vaccines for children under 5 until @US_FDA authorizes them. Don't believe that will happen until maybe some time in May?

26. Doran Fink from @US_FDA is addressing Covid vaccines for kids. Says FDA is aware of parents' desires to be able to vaccinate their kids.
"We are continuing to work towards that goal, which is incredibly important." I found his comments a bit confusing.

27. He said "once @US_FDA has one or more applications" it will move.
Haven't both Pfizer and Moderna applied already? Did I mishear this? Anyone?
#ACIP

28. Thanks to the various folks who filled in my mental gap on the issue of whether Moderna and/or Pfizer have actually submitted their applications for authorizations of Covid vaccines for kids under 5.

https://twitter.com/kshpil/status/1516859466175627264?s=20&t=8AaJ8G0CMZC90sIErfLqtw

29. This: @CDCgov's Sara Oliver is setting up #ACIP for a discussion about how to use boosters going forward. She makes the point there should be acceptance of what the country wants from giving added doses — to shore up protection against severe disease or to stop any disease?

30. Oliver notes with uptake of Covid vaccine has declined with each added dose. Fewer people got booster 1 than go the primary series. Hard to see this pattern changing with booster 2. #ACIP

31. Oliver tells #ACIP the @CDCgov would like the committee's thoughts on these questions.
Sarah Long: "We should not chase the rainbows" of hoping the existing vaccines can stop all infections. They cannot.

32. #ACIP member Matt Daley asked @US_FDA's Doran Fink what the timeline would be for updating the vaccine strain, if a decision to do that is needed. Fink said if an updated mRNA vaccines are wanted for this fall, the decision needs to be made by the beginning of the summer.

33. Fink did not know what the timeline would be for producing updated versions of viral-vectored vaccines.
One #ACIP member — maybe one of the non-voting members — said if there's going to be a recommendation to boost in the fall, hospitals need to know soon to plan.

34. #ACIP member Beth Bell says she's very concerned about "booster fatigue" and erosion of confidence in the efficacy of the vaccine. She says they need to be clear that for most people, the primary series (2 doses) plus 1 booster is still protective against severe disease.

35. The #ACIP meeting has concluded.