New York City health authorities have confirmed the first U.S. case of severe mpox caused by clade I-the more dangerous strain of the virus previously seen in the 2024 Democratic Republic of Congo outbreak.
The infected resident recently returned from international travel. Officials stress there is no evidence of local spread, and the risk to the general public remains low.
Clade I is known to cause life-threatening illness, unlike the milder clade II responsible for the 2022 global outbreak. Transmission occurs through close physical contact, including sexual activity, kissing, or respiratory droplets at close range.
The NYC Health Department urges high-risk individuals-particularly gay and bisexual men over 18 and those traveling to affected regions-to complete the two-dose JYNNEOS vaccine series. Vaccination within 14 days of exposure can prevent or reduce disease severity.
Symptoms typically appear one to three weeks post-exposure and include fever, swollen lymph nodes, and a painful blistering rash. In rare cases, complications may involve eye infections, neurological issues, or severe skin damage. Severe cases may be treated with the antiviral TPOXX (tecovirimat).