Human cases of Mpox date back to the 1970s in the Democratic Republic of the Congo, according to the National Institutes of Health. But in recent years the virus has spread globally, and the CDC says over 100,000 people have been infected with the clade II strain.

The U.S. has reported its first case of a more aggressive strain of mpox. The WHO declared the virus' spread a public health emergency in August.

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 public remains low,

The first known case of clade I mpox in the U.S. was recently discovered in a person in California, the Centers for Disease Control and Prevention said Saturday.

California has detected the country’s first case of a new mpox strain in a person who recently traveled from Eastern Africa