It’s always stunning how quickly we move from the height of summer to the rush of “back-to-school” season — that cusp between summer fun and business as usual. But is this a “business-as-usual” year?

With recent headlines announcing recommendations and potential changes to vaccine requirements, parents may wonder if New York State has altered the immunization schedule required for school attendance, which is determined by recommendations of the Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control (CDC).

Although the ACIP announced recently it will reexamine the children’s schedule, as of now, the federal guidelines have not been altered.

Linda You, director of clinical services for The Floating Hospital, said “There is a lot of fluidity surrounding vaccines right now as the ACIP dynamics are changing,” leading to known and probable changes in the coming months. These include the removal of thimerosal in annual flu vaccines, which the ACIP voted on in June. According to the CDC website in a post from last December, “Thimerosal use in medical products has a record of being very safe. Data from many studies show no evidence of harm caused by the low doses of thimerosal in vaccines.” The mercury-containing preservative has generated marginal distrust of the vaccines containing it, which in the United States is only in multi-dose annual flu vaccines to prevent cross-contamination. The Floating Hospital has “always had preservative free vaccines, more for ease of administration than for concern about thimerosal,” Ms. You said.

In addition to annual flu and Covid shots, we continue to offer recommended childhood vaccinations such as measles, rubella, and mumps, chicken pox, polio, pneumonia, hepatitis B, meningitis and diphtheria, tetanus and whooping cough. We work with the Vaccines for Children (VFC) program, which provides free shots to children who are uninsured, underinsured, Medicaid eligible or from Indigenous descent. According to recent news reports, cuts to the CDC and other funding may affect this program, but no adjustments to its CDC webpage or announcements have been made to date.

Measles, then and now

Ms. You also anticipates a possible change to the MMR schedule. “This hasn’t been done yet,” she said. “But there’s a lot of discussion about more potential changes in the childhood vaccination schedule,” which doctors and public health officials are monitoring.

There has been some concern about whether the number and variety of vaccines children now receive is safe. According to a pamphlet created in collaboration with the Yale School of Public Health, children under 2 received vaccines for seven diseases in 1983. Although safe and effective, these vaccines targeted more than 3,000 antigens in total. “Over the years, scientists got smarter at targeting viruses and bacteria—exposing children to fewer and fewer parts of the microbe (antigens) to stimulate the immune system,” it stated. Now, children under 2 receive vaccines against 15 diseases, but the formulas target only 180 antigens, resulting in far less stress on the immune system.

The MMR shot has a potential for increased seizure risk, but very slight, according to data used by Yale. Out of an average of 10,000 children receiving MMR shots, three had fever-related seizures and there were .035 allergic reactions. Compare it to Yale’s data on the risks of actual measles infection, which in an average 10,000 children results in 10-30 deaths, 2,000 hospitalizations, 10 cases of brain swelling, 1,000 ear infections potentially causing permanent hearing loss and 500 cases of pneumonia.

These risks gain urgency against the backdrop of this year’s very real outbreaks and 1,319 confirmed measles cases (862 of them in children) in the United States as of July 22. The largest outbreaks began in Texas (with cases eventually spreading to several more states) leading to the deaths in that state of two unvaccinated children without any known underlying health conditions. These consequences have demonstrated the predicted risk of not inoculating against measles to be tragically accurate.

While measles was declared eradicated in 2000, the hesitancy to vaccinate children has increased in recent years, resulting in a drop from a 95.2% vaccination rate in kindergartners entering school in 2019 nationwide to 92.7% in 2023. This has moved our country below the 95% rate required for herd immunity and put 280,000 students at risk, according to CDC data. Herd immunity protects the vaccinated as well as those too sick or too young to be vaccinated. Measles, which is highly contagious, can be brought here by international travelers to and from countries where it is still active.

Covid and mRNA shots

Other recent developments include a new guideline on Covid vaccines, where it is no longer “routinely recommended” for children. It is still recommended for those aged 65 and older. The concern here is increased risk of myocarditis, an enlargement of the heart, or pericarditis, enlargement of the outside lining of the heart. The Food and Drug Administration has recently updated its warning on Covid-19 shots “to convey that the observed risk of myocarditis and pericarditis following vaccination with mRNA Covid-19 vaccines has been highest in males 12 through 24 years of age.” Additionally, the FDA will require new language highlighting the incidence of the two conditions after administering the 2023-24 version of the Covid vaccines was “approximately 8 cases per million in individuals 6 months through 64 years of age and approximately 27 cases per million doses in males 12 through 24 years of age.”

The mRNA (or messenger RNA) technology, despite being discovered in the 1960s and developed in the 1970s, is often perceived as a radically new method of making vaccines. Its successful use against Covid-19 was the first time it was used on a large scale in the United States. Previously it had been employed in fighting Ebola in Africa and in some other rare diseases. According to the Johns Hopkins Bloomberg School of Public Health, “With Covid, this technology got its moment and has proven to be extremely safe and effective.”

The vaccines work by “giving your body instructions to make a small part of the virus so your immune system can generate tools to fight an infection if it sees the virus again in the future,” according to the Cleveland Clinic. This process is focused on just that one function and poses no danger or compromise to the body’s overall DNA. The Covid success story has inspired research into many other applications from annual flu shots to HIV and even cancer. A vaccine to address a potential bird flu pandemic was under development for use by the U.S., but the federal contract with Moderna was cancelled recently.

The Cleveland Clinic notes, “it can take time to accept something that’s different from the old, familiar way of doing things that we’re all comfortable with. But researchers have been developing mRNA technology for decades. It’s allowed scientists to create safe, effective vaccines faster than ever before. This means when there’s an outbreak of severe illness, we can potentially have the protection of vaccines in a matter of months instead of years.”

The uncertainty caused by the recent announcements and changes in staff and committees at the CDC has prompted the American Medical Association and dozens of other allied organizations, including the American Academy of Pediatrics, to sign a joint letter calling on insurers, hospitals, and public health agencies “to ensure vaccines remain available to patients without cost sharing.”

Citing last year’s severe flu season, the AMA said, “The health and safety of the public remains our top priority, and we will continue to support evidence-based immunizations to help prevent severe disease and protect public health.”

“This continues to be The Floating Hospital’s stance on vaccines: the benefits outweigh the risks, and we will continue to support vaccination as a core component of our primary care prevention model,” Ms. You said.