US health officials reported Saturday the first known case of a person infected with the new mpox strain in the country.
The person acquired mpox while traveling to east Africa and was treated for a mild illness in San Mateo, California, according to health officials. The person is isolating at home and is recovering, and there is no evidence that mpox is spreading in the United States.
The risk to the public remains low. Mpox is transferred through close contact, including sexual contact, kissing, cuddling or other skin-to-skin contact. Symptoms include blistered skin rashes, ulcers on the body and flu-like symptoms, like headache, backache and muscle ache.
Mpox has been spreading in the US since 2022, when the World Health Organization (Who) declared a global health emergency for the spread of the disease, which is endemic to central and western Africa.
In August, Who declared another global health emergency over a new strain of mpox, known as clade Ib, that has been spreading primarily in the Democratic Republic of the Congo (DRC), Uganda and Burundi. Since late September, more than 3,100 cases of mpox clade Ib have been reported globally.
Symptoms of the new strain appear to be more severe and are more likely to lead to death. Mpox is still spreading at low levels in the US.
“Given the very low risk to the public of exposure to [the new mpox strain], the standing guidance for preventing mpox has not changed,” said Dr Kismet Baldwin-Santana, the San Mateo county health officer, in a statement.
Cases of travelers with the new variant have been reported in Thailand, Germany, India, Sweden and the UK. In the UK, four individuals in the same household have been confirmed to have the new strain – the only four known cases in the country.
There is a two-part vaccination to prevent mpox. The Africa Centres for Disease Control and Prevention has called for 10m doses of the vaccine by 2025 to respond to the epidemic, particularly in the DRC. The DRC had about 30,000 suspected mpox cases and 859 deaths at the beginning of October, which accounted for 80% of all cases and 99% of all deaths in Africa this year.
