Montgomery County health officials are conducting contact tracing after the first confirmed case of measles in Pennsylvania this year was found over the weekend in an unvaccinated child.
Employees with the Montgomery County Department of Health and Human Services Office of Public Health are identifying individuals possibly contacted and notifying them of potential exposure to measles. They're also assessing for vaccination status and the risk of infection.
County health officials have not released the age, gender or name of the unidentified child with measles, or provide an update on Monday. But they have listed locations the child visited during their infectious period.
Anyone in these locations could have been exposed to the highly contagious disease:
About Measles
Measles is an extremely contagious virus that lives in the mucus membranes of the nose and throat of infected people. Measles can be transmitted from person to person through coughing and sneezing.
Measles virus can remain in the air and on surfaces for up to two hours after an infected person leaves the area. If someone breathes in the contaminated air or touches an infected surface and then touches their eyes, nose or mouth, they can become infected.
Measles is a reportable disease in Pennsylvania. Last year there were four cases and all of them involved international travel as the initial source of infection, according to the commonwealth. No measles outbreaks were reported in the state last year.
Philadelphia Public Health Department experienced a measles outbreak that spiked between December 2023 and January 2024 and impacted nine people, eight of them Philadelphia residents.
Measles symptoms
On average, symptoms appear between one and two weeks after exposure, but this can be as long as three weeks.
Measles typically begins with a fever of 100.4 degrees Fahreheit or higher that lasts for several days, followed by a cough, runny nose and watery eyes (conjunctivitis), according to the Montgomery County Office of Public Health.
Two or three days after symptoms begin, tiny white spots may appear in the mouth. Three to five days after symptoms begin, a flat red spotted rash appears beginning on the face at the hairline and spreads downwards to the neck, trunk, arms, legs and feet.
The flat red spots may also be joined by small, raised bumps.
What we know about U.S. measles cases so far this year
As of Feb. 27, 164 measles cases have been reported in nine states including New Jersey and New York City, according to the U.S. Centers for Disease Control in Atlanta.
So far this year, and 153 of 164 reported cases are outbreak-associated, meaning they involved three or more related cases. In 95% of the confirmed cases the individual was unvaccinated or vaccination status was unknown.
One death was reported in an unvaccinated child. A total of 32 people, most under age 5, have been hospitalized so far this year with measles.
Last year there were 285 cases of measles reported in the U.S., mostly in people who were unvaccinated or whose vaccination status was unknown; of that total 198 cases were outbreak-associated, according to the CDC.
Approximately 40% of cases last year, 114 total, resulted in hospitalization for isolation or complications. Most cases were in individuals ages 19 and younger.
Know your risk for measles
For individuals who are properly immunized against measles, the risk of contracting the disease is minimal. Individuals who believe they were exposed can:
Who is considered immune to the measles, and who is not
Individuals are considered to be immune to measles if:
The following groups of people are potentially susceptible to measles:
Reporter Jo Ciavaglia can be reached at [email protected].