U.S. records most measles cases in single year since record 2019 wave

The U.S. has seen at least 308 measles cases so far this year, according to figures published Friday by the Centers for Disease Control and Prevention, marking the most infections reported nationwide in a single year since a record 2019 wave.

More than 90% of the cases have been from a growing outbreak in Texas and neighboring New Mexico – totaling at least 284 measles infections in the CDC’s data.

Two additional “probable” cases linked to the outbreak this week in Oklahoma have so far not been added to the CDC’s tally.

This year’s total of 308 cases now tops the 285 infections reported for all of last year, which saw a large outbreak in a Chicago migrant shelter.

A total of 1,274 cases were reported in 2019, according to the CDC, the most reported in the U.S. in decades. Health officials were alarmed at the time about large and ongoing outbreaks, driven mostly by spread in undervaccinated communities in New York.

Before this year, the last U.S. measles death in the CDC’s death certificate records was also in 2019. This past February, a child who was hospitalized with measles died in West Texas. This month, an unvaccinated adult in New Mexico tested positive for measles after their death, although health officials said the official cause of death is still under investigation.

The U.S. is not the only country seeing an increase in measles cases. A separate record outbreak in Canada has driven up cases across the Americas, prompting the World Health Organization to warn earlier this month that the region’s “elimination status” was at risk.

Health officials in Europe and Asia also warned this week of an increase in measles cases there, amid gaps in immunization coverage.

“Measles is back, and it’s a wake-up call,” Dr. Hans Henri P. Kluge, the World Health Organization’s regional director for Europe, said in a statement. “Without high vaccination rates, there is no health security. As we shape our new regional health strategy for Europe and central Asia, we cannot afford to lose ground. Every country must step up efforts to reach under-vaccinated communities.” 

The CDC urged Americans this month, in a health advisory ahead of the travel season this spring and summer, to make sure they are up to date on their measles vaccinations.

Outside of Texas and New Mexico, most measles cases in the U.S. so far have been linked to unvaccinated or undervaccinated people exposed to the virus during international travel.

Maryland, New York state and Vermont were added to the CDC’s tally of measles cases this week. 

Alaska, California, Florida, Georgia, Kentucky, New Jersey, New York City, Pennsylvania, Rhode Island and Washington state had previously reported infections this year in the agency’s tally.