The US may be heading to a "dangerous vaccination tipping point," with immunization rates falling so low that population-level immunity is now at risk, and we will likely see thousands of needless deaths this respiratory virus season, two top officials for the Food and Drug Administration warned in a recent JAMA commentary.

FDA Commissioner Robert Califf and top FDA vaccine regulator Peter Marks noted the profound benefits of vaccines—which save millions of lives in the US each year—and their established safety, which is monitored both passively and actively through multiple overlapping federal safety monitoring systems. And yet, "an increasing number of people in the US are now declining vaccination for a variety of reasons, ranging from safety concerns to religious beliefs," thanks to the rise of anti-vaccine misinformation spread on social media and elsewhere on the Internet.

Data from the Centers for Disease Control and Prevention last year found that, for the third consecutive year, vaccination rates among kindergartners had continued to slip, with rates of non-medical vaccination exemptions rising to an all-time high. There are now 10 states with vaccination exemption rates over 5 percent, meaning that even if clinicians and health officials manage to vaccinate all non-exempt children, the state will not be able to reach the target of 95 percent coverage needed to curb the spread of disease on a population level.

Califf and Marks lamented that the efficacy of vaccines that prevent "disturbing" suffering and deaths from vaccine-preventable diseases, such as the extremely contagious measles, is no longer visible for people in the US. Thus, vaccines' benefits are under-appreciated, and vaccination rates are slipping, particularly in small pockets of the country.

"Regrettably, pediatric vaccine hesitancy now has been responsible for several measles outbreaks in the US, including a recent one in central Ohio involving local-acquired cases in 85 children, 36 of whom (42 percent) had to be hospitalized for complications," Califf and Marks write.

A measles outbreak is ongoing in Philadelphia, where an unvaccinated person who contracted the virus outside the US exposed other unvaccinated people at the Children’s Hospital of Philadelphia and an area daycare. So far, eight cases have been confirmed (one adult and seven children), six of which were hospitalized. Some of the cases occurred when an infected unvaccinated child broke quarantine and attended the daycare.

While childhood vaccination rates suffer and bygone diseases flare, there's also concern for older people and more familiar diseases. The respiratory virus season is now peaking. Influenza-like illness activity—which can capture not just flu but also RSV and COVID-19—is high and rising throughout much of the country, posing a high risk to older people. Flu is infecting the most people right now, but COVID-19 is causing more than six times more deaths, with over a thousand deaths a week in recent weeks. Yet, the CDC estimates that only about 19 percent of adults have gotten the latest COVID-19 vaccine booster so far, while nearly 45 percent have gotten their annual flu shot.

Califf and Marks pose the question of what can be done to reverse course, and they point to a possible solution of calling on doctors, nurses, and even pharmacists to speak up about the benefits and importance of vaccination. Clinicians who provide care remain the most trusted sources of information for health decisions, they write.

"We believe that the best way to counter the current large volume of vaccine misinformation is to dilute it with large amounts of truthful, accessible scientific evidence," they conclude. They called on health care providers to take every chance to help people make well-informed decisions about vaccinations. "By doing so, we can both help prevent pediatric infectious diseases and dramatically reduce the harm from pathogens such as COVID-19, influenza, and respiratory syncytial virus [RSV] disease before we have another large wave of any of these vaccine-preventable illnesses."