Health officials in California have confirmed the first domestic case of a more severe form of MPOX in a traveler from East Africa, according to the U.S. Centers for Disease Control and Prevention.
According to the agency, the risk to the public remains low. Health officials are working to identify people who may have been exposed to the person who recently traveled from East Africa and was treated at a local medical facility shortly after returning to the U.S., the CDC said.
Casual contact — including while traveling — is unlikely to pose significant transmission risks, the agency noted.
This is the first confirmed case in the US of a strain, or clade, of the virus called clade 1b.
Another strain, clade 2b, was primarily responsible for the 2022 global outbreak. During the outbreak, mpox spread mainly through close sexual contact — and a strong vaccination effort would help slow the surge of cases. This less severe version continues to circulate at low levels in the US. The CDC does not currently recommend booster shots for those who are considered high risk and have already been fully vaccinated.
Clade 1b was recently found in Congo in September, likely responsible for a growing outbreak in Africa that led the World Health Organization to declare a global public health emergency. Initial data indicate that this clade is more serious and may spread through other contact routes in households and often to children.
People with MPox, formerly known as monkeypox, often develop a rash that can be on the hands, feet, chest, face, mouth or near the genitals, according to the CDC.