Wyoming is reporting its first measles case in 15 years as the infectious disease continues to spread across the United States.
The state’s Department of Health said on Tuesday that it had confirmed a case in an unvaccinated child in Natrona County, which is located in the central part of the state and includes the town of Casper.
The pediatric case is the first reported in Wyoming since 2010, according to the WDH.
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It’s unclear how the child became sick, and no other identifying details were provided including name, age or sex.
A release from the WDH said the child was infectious while in the emergency department waiting room at Banner Wyoming Medical Center in Casper on Thursday, June 24, from 11 a.m. MT to 1 p.m. MT and on Friday, June 25, from 12:55 p.m. MT to 2:55 p.m. MT.
Julio Cortez/AP, FILE – PHOTO: A sign is seen outside a clinic with the South Plains Public Health District, on Feb. 23, 2025, in Brownfield, Texas.
The WDH said it is working with Banner Wyoming Medical Center to notify individuals who may have been exposed to measles during those times.
“We are asking individuals who were potentially exposed to self-monitor for measles symptoms for 21 days past the exposure date and consider avoiding crowded public places or high-risk settings such as daycare centers,” Dr. Alexia Harrist, state health officer with the WDH, said in the release.
Wyoming is the 37th state to confirm a case of measles this year as infections near a 30-year high in the U.S.
As of Wednesday morning, a total of 1,227 cases have been confirmed, according to data from the Centers for Disease Control and Prevention (CDC).
The U.S. is currently on track to surpass the 1,274 cases seen in 2019 and is expected to see the highest number of cases since 1992.
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There have been three confirmed deaths so far this year, two among unvaccinated children in Texas and one among an unvaccinated adult in New Mexico.
Among the nationally confirmed cases, the CDC says 95% are among people who are unvaccinated or whose vaccination status is unknown.
Meanwhile, 2% of cases are among those who have received one dose of the measles, mumps and rubella (MMR) vaccine and 3% of cases are among those who received the recommended two doses, according to the CDC.
“Measles is one of the most contagious diseases we know, but it is preventable,” Harrist said in the release. “The MMR vaccine is safe and highly effective, providing long-lasting protection. Two doses of MMR vaccine are about 97% effective in preventing measles, and we recommend that all Wyoming residents ensure they and their children are up to date on MMR vaccinations.”
As of 2023, the latest year for which data is available, at least 93% of kindergartners in Wyoming had received at least one MMR dose, including 96% of kindergartners in Natrona County, where the new case was confirmed, according to the WDH.
