Mpox cases in New York City have increased substantially since October 2023, mostly in people who haven’t been vaccinated or have only received one dose, the New York City Department of Health and Mental Hygiene (NYC Health) said in a May 3 health alert.
For most of 2023, the city averaged about 2 to 20 cases per month, but since October, cases have averaged 36 per month, with a peak of 51 in January. Of 256 cases reported since October, 73% were unvaccinated or had only received one dose, and 94% involved men who have sex with men. Most were Black and Hispanic men ages 25 to 44. Most cases were mild, and 10 people were hospitalized.
The health department urged healthcare providers to continue to encourage and offer vaccine to at-risk groups, especially those with HIV or other immunocompromising conditions, or to refer them to vaccination sites. Health officials acknowledged the transition of the Jynneos vaccine to the commercial market, noting that no-cost federally funded supplies will be available until early summer.
A reminder to be on the lookout for clade 1 cases
Also, it warned providers about the risk of the more severe clade 1 virus—currently fueling an ongoing severe outbreak in the Democratic Republic of the Congo (DRC)—to the United States. So far, the clade 1 outbreak strain hasn’t been detected outside endemic countries in Africa. The global outbreak involves clade 2, which typically results in milder symptoms.
However, NYC Health urged providers to be alert for people who have mpox symptoms and a history of travel or epidemiologic links to the region, including the DRC.