The rapidly rising US measles outbreak grew to 2,777 cases today as the Centers for Disease Control and Prevention (CDC) confirmed 211 new infections in its weekly update.
The increase is more than double that seen last week, when the agency added 101 cases to the total, after adding 94 the week before. Most of this week’s cases are in Pennsylvania and Ohio.
The CDC noted 36 outbreaks, which might be an anomaly, as a week ago the agency had logged 38 for the year. Last year saw 48 measles outbreaks, defined as three or more related cases. Total cases for all of 2025 reached 2,289, which was the most since 1991 until the country surpassed that level a month ago.
All but 16 of this year’s cases have been locally acquired, with the rest tied to international travel. Cases have been confirmed in 45 states plus New York City and Washington, DC.
Of the 2026 cases, 19% involve children age 5 and under, and 66% involve kids and teens. Seven percent of patients have been hospitalized, compared with 11% in 2025. Among all measles patients, 94% are unvaccinated or have an unknown vaccine status.
No measles deaths have been reported this year. Last year, three people, including two children, died of measles, one of the most transmissible diseases known.
89 new cases in Pennsylvania, 73 in Ohio
Pennsylvania continues to be the country’s hot spot, which reported 89 of the newest cases. Of the state’s 379 cases for the year, at least 181 of those (48%) are in Lancaster County, the state’s hardest-hit county, according to today’s update from state officials.
Chester County has the second-most cases, 41, followed by Mifflin (25) and Lebanon (21) counties.
In addition, the outbreak has reached Allegheny County, though a case there is not yet part of the state’s Department of Health total. CBS News reports that a University of Pittsburgh Medical Center spokesperson said an unvaccinated patient was seen at the UPMC Children’s Hospital emergency department on both August 12 and August 18. It’s the first case in the county since 2019.
The Allegheny County Health Department said the patient is from outside the county and is in isolation. “The Health Department recommends that any person who is due for measles vaccination make arrangements to receive it from their medical provider,” officials said in a news release.
The Health Department recommends that any person who is due for measles vaccination make arrangements to receive it from their medical provider.
In neighboring Ohio, health officials have confirmed 142 cases so far this year, an increase of 73 this week. Ashtabula County has the most infections: 40. Fifteen Ohio counties are now affected, an increase of four this week.
Utah, the state with the largest active measles outbreak, had no new cases keeping its 2026 total at 518. The CDC measles map (below), however, lists 526 cases for Utah. Last year Utah recorded 197 cases.
Likewise, Washington state had no new infections (55 total), and neither did Arizona, whose total remains at 122. Virginia also held steady, at 177 cases.
