An outbreak of measles in Philadelphia is growing larger. This week, health officials announced a newly discovered case of the highly contagious viral disease in the area—the ninth reported to date. Many of these cases, including the latest one, have been traced back to a single day care center, and most if not all patients were unvaccinated against measles.
The outbreak appears to have begun in early December at the Children’s Hospital of Philadelphia. An infant was admitted to the hospital with fever; two days later, the baby developed the telltale rash associated with measles. By the time it was clear that the infant had measles, however, the infection had already spread to two other children nearby and later an adult.
The infant had recently traveled to a country where measles is prevalent, while all of the resulting cases occurred in unvaccinated people. One of the babies had been too young to receive vaccination yet (the first of two doses is recommended between 12 and 15 months of age). The older child’s family intentionally avoided measles vaccination, and the parents also refused proactive treatment that could have prevented infection following exposure, according to The Philadelphia Inquirer; one of the parents subsequently contracted measles.
Health officials requested that people who caught or were potentially exposed to measles at the hospital isolate themselves until the risk of further transmission had passed. However, they later learned that one of these families had refused to comply and sent their infected child to attend the Multicultural Education Station Day Care in Philadelphia. The child then sparked a new chain of infection there.
This latest case, announced by health officials Tuesday, is reportedly the fifth associated with the day care and the ninth overall reported recently. Officials haven’t provided any further details about the new case yet, including the person’s current medical condition, age, or vaccination status. Of the eight previous cases, all were unvaccinated, while six were hospitalized but later discharged. Another case, found in the neighboring state of New Jersey’s Camden County last week, appears to be unconnected to the rest, raising concerns that further outbreaks could be on the way.
The measles, mumps, and rubella (MMR) vaccine is very effective at preventing infection from measles. In 2000, with the help of routine childhood vaccination programs, the U.S. successfully eliminated measles within the country. To this day, national vaccination coverage of the MMR shot remains high. But measles is still common in many parts of the world, and cases will occasionally be imported to the U.S. from elsewhere. Since the extremely contagious virus can easily spread through vulnerable populations, outbreaks can still happen in pockets of less-vaccinated communities.
Flagging vaccination rates around the world have led to the resurgence of measles in places where it was diminishing. And even the U.S has faced the very real possibility of the disease being a local threat again. Measles isn’t especially deadly, but it can be more life-threatening to younger children. Other serious complications include pneumonia, encephalitis, and the possible loss of immunity to other infectious diseases. In 2022, an estimated 136,000 people worldwide died from measles, according to the World Health Organization—a 43% increase from the previous year.
The level of MMR vaccination coverage in Philadelphia is around 93%, which should keep these outbreaks from becoming a danger to the general public. But the city’s health officials have begun to host free vaccination drives in response to the outbreaks.
