An interesting week with the FDA VRBPAC meeting and release of a few new studies, but still no word from CDC on relaxing covid testing for asymptomatic individuals. Bottom line though, some more reasons to remain optimistic. Let's dive in.
RESP-NET
Trends continue downward overall as well as individually for covid, flu, and RSV in RESP-NET. This bodes well, although in the pandemic era anything seems possible. Of course still worthwhile to get flu and covid vaccines if eligible.
You might be interested to have a peek at the WHO influenza information, what is pictured below is current as of January 8. It is more or less a typical global flu picture.
As you can see, southern hemisphere activity is low for the most part, with a predominance influenza B and A H1N1pdm09 strains rather than the AH3N2 that predominated earlier. This change in strains is typical at the end of a flu season, both the B and H1N1 strains are well covered by this year's vaccine.
Covid Vaccine Horizon
As planned, the FDA VRBPAC did meet last Thursday. I was able to watch most of the day's proceedings. (It was a long day, you can watch a recording of the whole thing if you want!) Presentations by Pfizer, Moderna, Novavax, FDA, CDC, and others were followed by multiple questions and discussions, all very good. Rather than lull you to sleep with too many details, let me try to summarize key points which were all about simplification. First, the VRBPAC members voted unanimously to recommend harmonization of the covid vaccines going forward. By that I mean that each manufacturer will be providing the same vaccine for both primary series and boosters. So, we won't need to worry about whether a monovalent or bivalent vaccine is needed for a particular individual. If the FDA follows these recommendations and CDC/ACIP agrees, only the bivalent vaccines will be used for primary and booster series - we won't be able to access the monovalent mRNA vaccines. I certainly concur with this - we have had so much lost in translation in implementing covid vaccination in the US, it is too confusing for providers and vaccinees - and data are very reassuring that the bivalent mRNA vaccines have an excellent safety profile and at least equivalent efficacy, if not a little better. More on that later.
Not to be forgotten, we have a third vaccine from Novavax also authorized in the US. It is an adjuvanted vaccine that does not involve mRNA technology, and studies have shown excellent safety and efficacy in adults. Pediatric studies have lagged considerably and the company did not present any substantive new data for young children.
What remains confusing still is how individuals with prior infection but no prior vaccination will be treated. Probably one dose of vaccine would suffice, but how do we verify prior infection for an individual? Also, how do we determine exceptions to what could be a recommendation for annual covid vaccination for most people? Those exceptions include elderly, immunocompromised, and perhaps young children. Will some of them be recommended to receive 2 vaccines per year? Although this is a move towards simplicity, none of this is easy, and the devil will be in the details. I hope the CDC and other agencies are up to the communication task.
Expect more updates on timing and composition of vaccines to be available in late summer/early fall. Churning out an mRNA vaccine targeting newer variants takes about 100 days, maybe a little longer for the Novavax vaccine. It looks like the VRBPAC will be meeting again around May. We should all be very thankful for the efforts of VRBPAC staff and committee members.
Advice for Immunocompromised
Speaking of communication (pun intended), CDC has a nice graphic and somewhat clearer guidance for immunocompromised folks.
This definitely helps, but we all know that not all immunocompromise is equal, so the vaccine nuances (especially whether to administer subsequent doses once or twice a year) will be tough to explain for those with milder underlying conditions.
New Studies of Bivalent Covid Vaccines
Last week saw publication of three updates of results of bivalent covid boosters; all were discussed at the FDA meeting. First, a group at the University of North Carolina reported state data suggesting bivalent vaccine efficacy was pretty good against some of the newer omicron variants. The bivalent boosted individuals (study included ages 12 years and up) had better protection against severe infection than did those who received the monovalent booster. However, numbers were small resulting in wide confidence intervals, and as always protection lessened with longer time after boosting.
CDC reported early estimates of bivalent booster protection against BA.5 and XBB/XBB.1.5 sublineage variants in adults. The study had the same caveat about small numbers and wide confidence intervals, but again a suggestion that the bivalent booster might be performing better than the monovalent booster for these newer omicron variants.
Finally, a study just looking at the Pfizer vaccine showed somewhat better serum neutralization activity against the newer variants in adults who received the bivalent booster compared to those who received just the monovalent booster. This is an important study but less helpful since it is looking at a surrogate marker (neutralization levels) rather than true vaccine efficacy.
More Good News About mRNA Vaccines in Children
A large meta-analysis published last week provides more information about the excellent safety and efficacy of covid mRNA vaccines in children in the 5-11-year-old age group. Benefits far outweigh any risks from these vaccines.
Vaccine Conversations: AAP to the Rescue
The American Academy of Pediatrics published a 49-page report on methods for productive discussions of vaccines with families. If you don't have time to wade through that, AAP will have a 1-hour webinar this Thursday, February 2. I don't think you need to be an AAP member to attend.
Hope
The line "hope springs eternal" is buried somewhere in Alexander Pope's poem An Essay on Man. I also learned that it was the title of a 2018 indie film. I'm not planning to look into either Pope's poem or the movie. However, I can recommend the book I'm reading now, Sea of Tranquility by Emily St. John Mandel, especially if you've read any of her earlier books. It's contains a story of a fictional pandemic, but since I haven't finished it I don't know whether the ending is hopeful or not!