Cases of the highly transmissible disease have reached a 35-year high in the US, with nearly 3,000 confirmed infections in 2026 so far. The first two measles-related deaths of the year were recorded in Pennsylvania, right as the school year is getting going. With vaccination rates dropping across the country, parents of kids who aren’t able to get vaccinated or don’t mount a strong enough immune response due to weakened immune systems are weighing whether it’s safe enough to go to school.

While it’s not known exactly how many US children have compromised immune systems, a study by the Centers for Disease Control and Prevention estimated that 2.6 percent of children are immunocompromised. Immune deficiencies can have genetic causes or secondary reasons, such as chemotherapy for cancer treatment.

Schiano’s kid is among them. Her 10-year-old has mitochondrial disease. The family lives in Chester County, Pennsylvania, which has the second-highest number of measles cases in the state right now. Schiano has been closely monitoring the vaccination rates in her son’s school district, which have dipped below the 95 percent threshold needed for community protection against measles. Measles is breaking through in places where vaccination has dropped below that threshold. In neighboring Lancaster County, for example, just 87.6 percent of kindergartners are fully vaccinated against measles and 83.3 percent of seventh graders are.

Her son can’t be vaccinated, and he receives weekly infusions of immunoglobulin—concentrated antibodies from donated human blood plasma—to help his body fight infections.

“Measles is dangerous for anyone, but for him, this absolutely could be life or death,” she says.