“Infected people are contagious from 4 days before the rash starts through 4 days afterward. The incubation period for measles, from exposure to fever, is usually about 7-10 days, and from exposure to ...

Pennsylvania’s first measles case of 2025 has been reported in Montgomery County — outside of Philadelphia. The Montgomery County Department of Health and Human Services Office of Public Health said ...

As new cases are reported, our maps and illustrations show the spread of the virus and how infections can run through a ...