Measles vaccination rates among kindergarten students in the Philadelphia region have been declining since the COVID-19 pandemic, and are now below the so-called herd or community immunity rate needed to keep the highly contagious virus from spreading.

Medical experts say that 95% of a community must be vaccinated against measles to keep the disease from circulating, even at low levels. Vaccination rates among kindergartners in Philadelphia, Bucks, Chester, and Delaware Counties had all dipped below that critical threshold by the beginning of the 2023-24 school year, according to the most recent data available from the Pennsylvania Department of Health. In Montgomery County, 95.2% of kindergartners received two doses of the MMR (measles, mumps, and rubella) vaccine.

The downward trend began during the pandemic, when families avoided nonurgent medical appointments and were advised to stay home. But vaccination rates have continued to decline amid vaccine misinformation and new access challenges.

“It’s a perfect storm,” said Leslie Kantor, chair of the department of urban-global public health at Rutgers University. “The effect of that early time in the pandemic, when people were fearful of health-care facilities, combined with increased vaccine hesitancy, skepticism, and disinformation.”

Recent outbreaks in Texas and confirmed measles cases in Montgomery County and New Jersey have drawn attention to the importance of having high vaccination rates. Children’s Hospital of Philadelphia on Wednesday said a patient who visited its emergency department was later diagnosed with measles. An outbreak in Philadelphia last year sickened nine people and sent seven to the hospital.

President Donald Trump’s administration has been under scrutiny for its response to the Texas outbreak and its messaging on vaccines. Newly appointed Health and Human Services Secretary Robert F. Kennedy Jr. has referred to vaccines as a personal choice. The administration on Thursday withdrew its nomination of Dave Weldon to lead the Centers for Disease Control and Prevention amid congressional concern about the Florida doctor’s comments skeptical of vaccines.

The CDC recommends children receive their first dose of the measles vaccine between 12 and 15 months, and a second dose at 4 through 6 years. Health officials recommend vaccinations for children as early as six months if they are planning to travel internationally. Measles can cause a fever, coughing, and a raised, red rash. Young children are especially vulnerable to severe illness and death.

The Philadelphia region once boasted exceptionally high measles vaccination rates — in 2019, 97.4% of kindergartners in Philadelphia were vaccinated. Infectious-disease experts say the downward trend is troubling, especially as vaccination rates dip below the critical community vaccination rate. By 2022, measles vaccination among Philadelphia kindergartners had dropped to 92.8%, before rising to 94.5% in 2023.

A drop below the 95% critical community, or herd immunity, rate means outbreaks will become increasingly common, and the number of people who become severely ill or die could grow.

“We’re on track for vaccination rates to get worse rather than better,” Kantor said.

Contributing factors vary by community

The reasons families have not vaccinated their children vary greatly, experts said.

Transportation and access to primary-care doctors who are accepting new patients can be challenging for some.

In Upper Darby, for example, more than 80 languages are spoken, which means public health workers there must ensure they are making vaccine information available in many languages, said Deanna Dyer, health policy director for Children First, a Philadelphia-based nonprofit that advocates for public health and education issues.

The measles vaccine is among the childhood immunizations that are covered for free by health insurance and Medicaid, the government-funded health-care program for low-income families and people with disabilities. The vaccines are also available at no cost through public health departments. But people who are uninsured or who recently lost Medicaid coverage when states resumed annual renewals after the pandemic may not be aware they can still access free vaccines, Dyer said.

Immigrant families may fear seeking medical care as the federal government ramps up efforts to deport people who are undocumented. Medical facilities used to be considered off-limits to immigration raids but are no longer protected.

Public health educators say that partnering with trusted community leaders can help alleviate some vaccine fears.

In Lenni, a small, middle-income community in central Delaware County, public health outreach workers from Children First encountered political and religious opposition to vaccination.

Some Chester residents told Children First outreach workers that they skipped vaccines because they don’t trust medical institutions.

“It’s vital to collaborate with trusted community members to be the messengers,” Dyer said.

Camden County’s experience

In Camden County, local health officials mobilized to increase childhood vaccinations when they realized about two years ago that rates in the area had dropped during the pandemic.

“It was a matter of getting our communities back on schedule,” said Caryelle Vilaubi, the director of the Camden County Department of Health and Human Services.

School nurses and health department staff combed through vaccine records at schools and provided low-barrier clinics to ensure students were up to date on their vaccines, sending a mobile van to areas of the county with lower vaccination rates.

At the beginning of the summer, health officials found that 1,798 students in the Camden City School District were missing one or more required vaccines for the coming school year. By last month, that number was down to 75, said Dan Keashen, a spokesperson for the county.

All told, the county conducted 26 vaccine clinics with schools that requested a visit from the van, administering 329 vaccines in two months last summer. About 95% of kindergartners in schools were up to date on all childhood vaccinations for the 2023-24 school year.

Amid the measles outbreak in West Texas and two local cases unconnected to that outbreak — plus three more cases reported in Bergen County — Vilaubi said it is imperative that local health officials strongly recommend vaccines — and ensure that residents know where and how to get one.

“It is a local department’s responsibility to not just come out with a clear message that vaccines are important, save lives, and reduce illness, but that they’re readily available at pharmacies and at our clinics for people who are un- or underinsured.”

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