Pennsylvania's measles outbreak is the largest in decades in the US

NEW YORK (AP) — Pennsylvania has surpassed 1,000 measles cases this year, state health officials said Monday, making it the largest state outbreak in more than three decades.

The U.S. is enduring its worst year for measles since 1991, with nearly 3,900 reported cases, according to the CDC. The nation has seen eight reported measles-associated deaths in the past two years — more than the combined total of reported deaths over the previous three decades.

Since the beginning of last year, large outbreaks have been reported in several states, including Texas and Utah, as well as South Carolina, which had the largest with 997 cases reported.

Health officials say Pennsylvania’s current outbreak started in April, west of Philadelphia. There have been 1,004 cases, including 198 hospitalizations and five deaths , state officials said.

Health experts attribute such outbreaks to low vaccination rates.

It's been decades since a U.S. state has seen an outbreak surpass 1,000 cases, stretching back to a multiyear outbreak in New York City in the early 1990s that infected more than 4,500 people.

The nation eliminated the domestic spread of measles in 2000 by maintaining high vaccination rates, but those rates have fallen in recent years to below the 95% coverage needed to prevent outbreaks.

In November, international health officials will meet to determine if the U.S. and Mexico have lost their measles-free status .

Measles is highly contagious. It spreads when people who have it breathe, cough or sneeze, and through contaminated surfaces. It also can linger in the air for two hours. Up to 9 out of 10 people who are susceptible will get the virus if exposed, according to the Centers for Disease Control and Prevention.

U.S. measles infections have been surging in recent years, as fewer kids get routine vaccines due to parental waivers, healthcare access issues and rampant disinformation.

Pennsylvania is not the only state with a growing problem. Neighboring Ohio has reported more than 200 cases this year. Like in Pennsylvania, some of the hardest-hit Ohio counties have significant Amish populations, which tend to have lower vaccination rates.

Meanwhile, CDC officials have quietly begun to acknowledge measles-associated deaths in Pennsylvania.

State officials in August announced that two unvaccinated residents died after being infected with measles.

The announcement quickly came under fire as a clash erupted between vaccine-promoting Democratic Gov. Josh Shapiro and U.S. Health Secretary Robert F. Kennedy Jr., a Trump administration appointee with a history of raising alarms about established vaccines.

Since then, Pennsylvania has reported three additional deaths.

But for weeks, the CDC — which Kennedy oversees — did not count any deaths on its measles data dashboard, instead saying it was seeking more information. That changed two weeks ago, when one death was finally counted, and again last week when a second was added to the agency's tally.

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