Measles is making a comeback this summer, with schools in 36 states and the District of Columbia at higher risk for outbreaks.
An ongoing measles outbreak in Oregon is the latest of 13 such clusters and 188 total cases so far this year emerging in 25 states and the District of Columbia, according to the Centers for Disease Control and Prevention.
That’s more than triple the measles outbreaks in all of 2023. More than two-thirds of those who contracted measles so far in 2024 have been age 19 or younger, and they represent 95 percent of those who have been hospitalized for the disease.
Overwhelmingly, the outbreaks have been spread among unvaccinated children and adults. CDC data show 36 states and the District of Columbia now have vaccination rates below the 94 percent threshold for herd immunity, in which enough people are vaccinated to prevent wide-scale spread of a disease.
Measles is significantly more contagious than COVID-19. Nine out of 10 unvaccinated people exposed to the disease will catch it.
“We’re seeing more reluctance [to immunize students] on all of the vaccine-preventable diseases, not just flu and COVID,” said Kate King, the president of the National Association of School Nurses and a school nurse in the Columbus, Ohio, city schools. “Politicization of vaccines has added another layer to vaccine hesitancy.”
That’s a concern, because measles was one of the biggest public health successes of the last century. Infections dropped from nearly a half-million each year in 1960, before the vaccine was developed, to less than 100 in 2000, when the World Health Organization declared it eradicated in the United States. Two doses of the measles, mumps, and rubella, or MMR, vaccine have been found 97 percent effective in preventing measles.
Whooping cough cases on the rise too
Flare-ups of previously contained childhood diseases like measles and pertussis (commonly known as whooping cough) have become both more common and more costly for school districts. (A 2023 measles outbreak in Washington state cost schools and local health agencies more than $1 million to contain.)
As of June, whooping cough cases have also tripled compared to the same time last year, according to the CDC, with infants and young children at highest risk.
Vaccination delays can lead to school absenteeism even if there isn’t an outbreak. In Ohio, for example, students are barred from attending class if they do not have updated immunization records by 14 days into the school year.
King advised school leaders not to rely only on parents to find out which students need updated shots. All 50 states, as well as Puerto Rico and the District of Columbia, have immunization records systems, which to varying degrees provide information from pediatricians and public health agencies on child vaccination.
Because vaccination has become a divisive issue for schools, King advised against issuing blanket warnings or censure to families who have not vaccinated their students.
“In-person conversations, one-on-one with families is probably the best approach,” King said. “Not, ‘Why aren’t you getting your kids immunized?’ but, ‘Tell me about your views on that.’ Because sometimes with what parents tell us, we can assuage their fears about immunization and just build that relationship between the families and the school nurse, which is probably the key.”
Parents who are reluctant to vaccinate often overestimate the risk of vaccine side effects and underestimate their effectiveness, King said.
“Past generations saw the death and the effects of those diseases ... like with measles, losing hearing and brain swelling,” King said. “Parents today have never really seen the effects of those diseases. So the myth that these diseases aren’t dangerous for children is another thing that we do need to talk about.”
Starting the school year with on-site clinics and immunization fairs can also help encourage families to update students’ immunizations, King said. Both local health agencies and federal grants through the National Vaccine Program can help cover the cost of the events.