A health alert has been issued in Philadelphia following an outbreak of measles. The chain of infection began in December with a child who had recently traveled abroad and was later diagnosed with measles at the Children’s Hospital of Philadelphia (CHOP). The Philadelphia Department of Public Health classified the case as ‘imported,’ but has not publicly identified the country of origin. Notably, the virus spread within the hospital, infecting three other individuals, including an unvaccinated child and their parent. This parent declined the medication, often offered to unvaccinated patients, which could have prevented the infection after exposure to measles.
The unvaccinated child attended a daycare center despite quarantine recommendations and four additional people subsequently contracted the infection at the center. Meanwhile, in Montgomery County, one individual, and possibly many others, were exposed to measles at two healthcare facilities. However, no cases have been confirmed in the county so far.
No individual diagnosed in Philadelphia had immunity to measles, indicating either a lack of vaccination or no prior exposure to the disease. This outbreak prompted a significant response. Four new patients were admitted to hospitals in addition to the two initial patients, with hospitals in the area on vigilant alert for more cases. Measles, a viral disease that can linger airborne for up to two hours after an infected person has left, poses a significant threat to communities, especially considering a single infectious person can potentially infect up to 90% of nearby non-immune individuals.
The tell-tale sign of measles, a red and blotchy rash, typically appears three to five days accompanied by high fever, cough, runny nose, and red, watery eyes. Among unvaccinated individuals, approximately one in five require hospitalization. Furthermore, one to three per 1,000 children who contract measles experience life-threatening complications such as pneumonia or brain swelling.
Vaccination is evidently the most reliable safeguard against the disease. A single dose of the measles-mumps-rubella (MMR) vaccine is 93% effective at preventing measles, while two doses up the efficacy to 97%, providing lifelong protection. Noteworthy is that in Philadelphia, at least 93% of children receive full vaccination against measles by the age of six. For non-immune individuals exposed to measles, timely administration of the MMR vaccine within 72 hours or immune globulin injection within six days of exposure can still prevent the disease.
Measles was declared eliminated in the U.S. in 2000, although isolated outbreaks occasionally occur, often imported from overseas. Misinformation, opposition to vaccination regulations, and COVID-induced hesitancy to visit healthcare facilities have contributed to a decline in immunization rates, a point underscored by Dr. Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Philadelphia. Offit emphasized that measles’ highly contagious nature makes it the first disease to re-emerge when immunization rates fall.