US has already had more measles cases in 2024 than all of 2023

The number of measles cases reported in the U.S. so far this year has already surpassed the total number of infections counted in 2023.

According to data released by the Centers for Disease Control and Prevention (CDC), 64 confirmed and suspected cases of measles had been reported across 17 states as of March 21. Last year, 58 total cases were reported in 19 states and Washington D.C.

This year's case count hasn't yet smashed records seen in the past decade. 2014 and 2019 stand out as particularly bad years, with more than 660 and 1,200 measles cases apiece; these high numbers partly stemmed from major outbreaks tied to Disneyland and to underimmunized, close-knit religious communities.

However, measles cases have rebounded significantly since 2020, when only 13 infections were reported in the U.S. And internationally, Austria, the Philippines, Romania and the U.K. are experiencing outbreaks, the CDC cautioned in a recent health advisory.

Related: Measles deaths jumped over 40% from 2021 to 2022, CDC reports

"Given currently high population immunity against measles in most U.S. communities, the risk of widescale spread is low," the advisory reads. "However, pockets of low coverage leave some communities at higher risk for outbreaks."

At the time of the advisory, issued March 18, 58 of this year's measles cases had been confirmed by the CDC. The vast majority, over 90%, were tied to international travel, the CDC reported, while some have been tied to domestic travel to Florida, according to CBS. Most cases were reported in unvaccinated children ages 1 year and older.

The CDC recommends that children receive their first measles-mumps-rubella (MMR) dose at 12 to 15 months old and a second shot between 4 and 6 years old. But kids at least 6 months old who will be traveling internationally should receive at least one dose of MMR vaccine before departing, according to the CDC.

Recently, the percentage of U.S. kindergarteners who have not completed their measles vaccination has grown, leaving an estimated 250,000 kindergartners susceptible to the infection each year for the last three years, the CDC reported. The goal is to have at least 95% of kindergarteners in a given community vaccinated, to minimize opportunities for the virus to find a vulnerable host and spread — but during the 2022-2023 school year, most states didn't hit that 95% target, in part due to an uptick in vaccine exemptions.

Similar dips in routine measles vaccinations are being seen around the globe.

"This is why it's urgent for us to sort of address vaccination so that we can really decelerate sort of the march of measles, given the global scenario as well as what we're seeing with some vaccination rates in the country," Dr. Demetre Daskalakis, director of the CDC's National Center for Immunization and Respiratory Diseases, told CBS.

This article is for informational purposes only and is not meant to offer medical advice.

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