The U.S. is having its worst year for measles spread in more than three decades, and the year is only half over.

As of Wednesday, the national tally reached 1,288, according to the U.S. Centers for Disease Control and Prevention (CDC), though experts caution the real number might be greater.

The latest figure is 14 more than the 2019 total, a year when the U.S. nearly lost its designation for eliminating this preventable disease—something that might happen again if the virus circulates unchecked for a year. However, this is still significantly lower than the 9,643 confirmed cases back in 1991.

The federal government stated that the CDC maintains its recommendation for the measles, mumps, and rubella (MMR) vaccine as the most effective protection against measles. The statement also highlighted ongoing efforts to support local initiatives designed to curb current outbreaks, alongside other actions. CDC teams have been deployed twice to Texas for direct outbreak intervention, with additional assistance provided to New Mexico and Kansas to control their outbreaks.

Fourteen states have active outbreaks; four other states’ outbreaks have ended. The largest outbreak started five months ago in undervaccinated communities in West Texas. Three people have died — two children in Texas and an adult in New Mexico — and dozens of people have been hospitalized across the U.S.

But there are signs that transmission is slowing, especially in Texas. Lubbock County’s hospitals treated most of the sickest patients in the region, but the county hasn’t seen a new case in 50 days, public health director Katherine Wells said.

“What concerned me early on in this outbreak was is it spreading to other parts of the United States, and that’s definitely what’s happening now,” she said.

In 2000, the World Health Organization and CDC said measles had been eliminated from the U.S. The closer a disease gets to eradication, the harder it can seem to stamp it out, said Dr. Jonathan Temte, a family physician in Wisconsin who helped certify that distinction 25 years ago.

It’s hard to see measles cases break records despite the widespread availability of a vaccine, he added. The measles, mumps and rubella vaccine is safe and is 97% effective at preventing measles after two doses.

“When we have tools that can be really helpful and see that they’re discarded for no good reason, it’s met with a little bit of melancholy on our part,” Temte said of public health officials and primary care providers.

Wells said she is concerned about continuing vaccine hesitancy. A recent study found childhood vaccination rates against measles fell after the COVID-19 pandemic in nearly 80% of the more than 2,000 U.S. counties with available data, including in states that are battling outbreaks this year. And CDC data showed that only 92.7% of kindergarteners in the U.S. had the measles, mumps and rubella vaccine in the 2023-2024 school year, below the 95% needed to prevent outbreaks.

State and federal leaders have for years kept funding stagnant for local public health departments’ vaccination programs that are tasked with reversing the trend. Wells said she talks with local public health leaders nationwide about how to prepare for an outbreak, but also says the system needs more investment.

“What we’re seeing with measles is a little bit of a ‘canary in a coal mine,’” said Lauren Gardner, leader of Johns Hopkins University’s independent measles and COVID-19 tracking databases. “It’s indicative of a problem that we know exists with vaccination attitudes in this county and just, I think, likely to get worse.”

Currently, North America has three other major measles outbreaks: 2,966 cases in Chihuahua state, Mexico, 2,223 cases in Ontario, Canada and 1,246 in Alberta, Canada. The Ontario, Chihuahua and Texas outbreaks stem from large Mennonite communities in the regions. Mennonite churches do not formally discourage vaccination, though more conservative Mennonite communities historically have low vaccination rates and a distrust of government.

In 2019, the CDC identified 22 outbreaks with the largest in two separate clusters in New York — 412 in New York state and 702 in New York City. These were linked because measles was spreading through close-knit Orthodox Jewish communities, the CDC said.

___

AP videojournalist Laura Bargfeld contributed to this report.

___

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education and the Robert Wood Johnson Foundation. The AP is solely responsible for all content.