About 20,000 people who attended a large religious gathering in Kentucky last month may have been exposed to measles, and undervaccinated attendees should quarantine and monitor symptoms for 21 days, the US Centers for Disease Control and Prevention said in a Health Alert Network Advisory on Friday.
The CDC alert was sent to clinicians and public health officials after the Kentucky Department for Public Health identified a confirmed case of measles in an unvaccinated individual on February 24. The individual had a history of recent international travel and attended a large religious gathering February 17 and 18 at Asbury University in Wilmore, Kentucky, as previously reported by CNN.
According to the CDC, an estimated 20,000 people attended the gathering from Kentucky, other US states, and other countries during those days, and an undetermined number may have been exposed.
“If you attended the Asbury University gathering on February 17 or 18 and you are unvaccinated or not fully vaccinated against measles, you should quarantine for 21 days after your last exposure and monitor yourself for symptoms of measles so that you do not spread measles to others,” the CDC said in the health advisory.
CDC officials also recommend unvaccinated individuals who attended the gathering speak to their health care provider about getting vaccinated after completing quarantine, as two doses of the MMR vaccine are about 97% effective at preventing measles.
For people who think they have measles or have been exposed to someone with the virus, the CDC recommends isolating from others and calling to notify a health care facility before arriving to be tested.
Measles is a highly contagious viral illness that begins with symptoms typical of many respiratory illnesses followed by a characteristic rash that usually appears on the face and spreads downward three to five days after symptoms begin.
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The CDC recommends that clinicians be on alert for cases of measles in anyone with compatible symptoms who attended the Kentucky event during February 17 or 18, had contact with an attendee or has recently traveled abroad, especially to countries with ongoing outbreaks.
“With declines in measles vaccination rates globally during the COVID-19 pandemic, measles outbreaks are occurring in all World Health Organization (WHO) Regions,” the CDC said in the health advisory.
In the United States, measles cases increased from 49 in 2021 to 121 in 2022, all among children who weren’t fully vaccinated, including outbreaks in Minnesota and Ohio.
CDC officials say the advisory in response to the Kentucky case highlights the “importance of early recognition, diagnosis, and appropriate treatment.”