The Vaccine Brief: RFK’s Testimony, RSV Wins, and Vaccine Warnings
What Matters This Week, May 15
I’m David Higgins, a practicing pediatrician and preventive medicine physician who cares for children, adolescents, and their families and studies how to improve how we communicate about and deliver preventive care and vaccines. This newsletter shares clear science, smart policy, and meaningful conversations, because the health of our communities depends on all three. If you haven’t already, hit the button below to stay in the loop with updates.
Hi community,
I am trying something a little different. Instead of “one big beautiful” post that combines headline commentary and a topic deep-dive, I’m trying something new: splitting the headlines into a separate update (The Vaccine Brief) while keeping deep-dives in the main newsletter.
It is also officially “Maycember” for me. On top of the usual work, school, and family routines, every day is packed with kids’ sports, art shows, graduations, and end-of-year events. And, to top it off, our basement recently flooded, so if I missed an important headline, now you know why.
Thanks to everyone who’s subscribed over the past few months since I started writing. Subscriber numbers have grown quickly, which I’ll optimistically take as a sign this content resonates (and not the work of a rogue AI bot). If you’re not yet subscribed, hit the button below so you don’t miss future updates.
So with that, here are several important headlines from this week and why they matter:
What Matters This Week (May 15)
RFK Jr. Testifies on the Hill
On Wednesday, the Health and Human Services Secretary, RFK Jr., testified before the House Committee on Appropriations and Senate Health, Education, Labor and Pensions Committee. This was supposed to be about the administration’s budget request and future HHS funding, but instead, he faced intense scrutiny for his record since taking the helm at HHS, and he was questioned about his views on vaccination amid a concerning number of measles cases in the U.S.
His opening remarks touched on popular priorities: safer food, rural hospitals, mental health, chronic disease, social determinants of health, and rebuilding public trust. These are important issues, and many Americans support those goals. However, HHS's actions under his leadership directly counter those stated priorities.
When asked if he would vaccinate his child against measles, he hesitated, stating, “Probably,” and added, “I don’t think people should be taking medical advice from me.” This is a perplexing response from our nation’s top health leader and someone who has not hesitated to share medical advice on unproven treatments for measles, raw milk consumption, or other medical topics.
In a particularly tense exchange, Kennedy defended his decision to hire David Geier, a discredited vaccine skeptic who previously practiced medicine without a license, to investigate supposed missing data from the CDC’s Vaccine Safety Datalink (VSD). The hiring of David Geier is something I have written about before here with
. Kennedy claimed Geier had access to information that “disappeared”—yet no independent evidence supports this claim. And importantly, the evidence showing no link between vaccines and autism spans decades, multiple countries, and millions of children, not just the VSD.Sadly, I don’t expect these hearings to change the direction of our federal health leadership.
RSV Hospitalization Rates are Down
And now for some good news!
According to a new Morbidity and Mortality Weekly Report (MMWR) report from the CDC, respiratory syncytial virus (RSV)-associated hospitalizations among infants (0-7 months) during the 2024-2025 season when both a maternal RSV vaccine and monocloncal antibody, nirsevimab, became widely available, were 28% and 43% lower compared to pre-COVID-19 pandemic seasons. This coincides with data from 5 countries published recently in The Lancet Child & Adolescent Health showing that nirsevimab is highly effective in preventing RSV-associated hospitalizations and ICU admissions.
And new studies (1,2) have shown high RSV protection rates:
Nearly 80% of U.S. infants were protected during the 2023–24 season.
CDC data from March 2025 showed 57% protection coverage nationally.
We still need to close gaps, but these are promising results. Pediatricians and parents alike know how disruptive RSV can be. I’ve admitted more kids for RSV than for any other infection. I hope one day to tell pediatric residents stories about the “old days” of packed waiting rooms, kids on oxygen, and exhausted parents navigating at-home care.
Puzzling Support for a Universal Flu Vaccine Project
The NIH has launched a major initiative to develop a universal flu vaccine—a “holy grail” that wouldn’t need annual updates to match circulating strains. On the surface, this is exciting news.
But there are concerns:
The project is based on an older whole inactivated virus approach, which historically comes with more side effects, not fewer.
It was funded with $500 million without a transparent review or the usual competitive vetting process.
The acting director of NIAID reportedly holds a patent on the technology.
I support innovation in flu vaccines, but I’m skeptical this particular project is the best use of limited funds. I genuinely hope to be proven wrong, but so far, it hasn’t met the bar for transparency or scientific rigor.
Pause in Chikungunya Vaccine
The FDA and CDC recommended pausing the use of a vaccine (Ixchiq) for chikungunya (pronounced chi-kin-GOON-ya) in adults aged 60 and older due to reports of severe adverse events, including neurological and cardiac issues. Chikungunya is a disease spread by mosquitoes, primarily in tropical climates, that can cause fever, a rash, muscle aches, and severe joint pain that can last months or years for some people.
Seventeen severe safety events after vaccination, including two deaths, have been reported globally, with six cases in the U.S., prompting an updated risk-benefit assessment and a pause on current recommendations.
Why does this matter? Beyond the implications for this vaccine specifically, this is an example of the robust vaccine safety surveillance systems in the U.S. and globally working as intended.
A related update: the FDA recently approved a second chikungunya vaccine (Vimkunya), which uses a different platform. The ACIP recommended its use at their April meeting, and according to a CDC website, on May 13, the HHS Secretary formally adopted the recommendation while the CDC is without a permanent director.
Notably, the CDC website does not yet mention other April ACIP recommendations, including the new pentavalent meningococcal vaccine (Penmenvy) and RSV vaccines for adults aged 50–59 at increased risk. These are usually adopted promptly and published in the Morbidity and Mortality Weekly Report (MMWR), so it’s worth watching for updates to confirm formal adoption.
Final Note
Thanks, as always, for being part of this community. I know there’s a lot going on, so I’ll keep tracking the headlines that matter and unpacking what they mean so you don’t have to.
-David
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