A resurgence of mpox this summer could be larger than last year’s caseload, the Centers for Disease Control and Prevention said in a warning to public health officials this week.
“The outbreak is not over,” the CDC alert stated, noting that springtime and summertime gatherings and festivals could lead to renewed virus spread. A new cluster of 13 cases is being investigated in Chicago, all among men, and four among people who recently traveled to New York City, New Orleans, or Mexico.
Mpox, formerly called monkeypox, is a virus that causes a rash and sometimes flulike symptoms. It is most often transmitted through sexual contact, but it can also be spread in nonsexual ways that involve contact with skin lesions or with saliva or upper respiratory secretions like snot or mucus, the CDC says. Most cases in the United States have been among gay or bisexual men, men who have sex with men, and transgender people.
Last year, the U.S. government declared mpox a public health emergency as cases peaked at 460 per day in August, infecting more than 30,000 people and killing 42 people. Public health officials worked to quickly distribute vaccinations to people at high risk for contracting the virus. The CDC says 23% of people most at risk of getting mpox have been vaccinated.
Vaccination does not necessarily prevent infection but can lessen the severity of symptoms. Nine of the men who were recently infected in Chicago were fully vaccinated.
“It’s important to remember that vaccines, while incredibly helpful, are not our only way to reduce the risk of contracting mpox,” Richard Silvera, MD, MPH, of the department of infectious diseases at Icahn School of Medicine at Mount Sinai, New York, told ABC News.
Other ways to reduce risk are “things like avoiding social and sexual contact if you have new skin lesions and asking your intimate contacts if they are experiencing symptoms or new skin changes,” Dr. Silvera said.
A version of this article first appeared on WebMD.com.