But the new outbreak is driven by clade I, which causes more severe disease.The subtype that’s responsible for most of the ongoing spread, clade Ib, is relatively new.

Most people fully recover after a few weeks, although the risk with clade I mpox has historically believed to be higher than with the clade II strain that has circulated in the U.S. since 2022.

The United States’ first known case of a more severe strain of mpox was confirmed in California, the US Centers for Disease Control and Prevention said Saturday. The risk of clade I mpox to the ...

While this the first case of clade I to be announced in the U.S., 3,004 cases of mpox clade II have been recorded since Jan. 1, 2024, according to CDC data.

The U.S. Department of Health and Human Services said in a statement that people who have received both doses of the mpox vaccine — along with people who have already had clade II mpox — “are expected ...

Clade I is generally considered more transmissible and more severe than clade II, which drove the global mpox outbreak that peaked in August 2022 and had a death rate of 0.2%.

Clade 1 has caused more than 600 deaths in Africa. There have been nearly 25,000 cases of the clade 1 version of mpox in Africa so far this year. IE 11 is not supported.

The Clade Ib version of the virus had not been detected outside Africa until last week, when a case in Sweden raised concerns about a wider outbreak.

The United States’ first known case of a more severe strain of mpox was confirmed in California, the US Centers for Disease Control and Prevention said Saturday. The risk of clade I mpox to the ...