US health officials report 1st case of new form of mpox in travellers

Health officials said on Saturday that they have confirmed the first US case of a new form of mpox, which was first identified in eastern Congo.

The person had travelled to eastern Africa and was treated in Northern California upon returning, according to the California Department of Public Health. Symptoms are improving, and the risk to the public is low.

The individual is isolating at home, and health workers are reaching out to close contacts as a precaution, the state health department said.

Mpox is a rare disease caused by a virus in the same family as the one that causes smallpox. It is endemic in parts of Africa, where people have been infected through bites from rodents or small animals. Milder symptoms can include fever, chills, and body aches. In more serious cases, people can develop lesions on the face, hands, chest, and genitals.

Earlier this year, scientists reported the emergence of a new form of mpox in Africa that spreads through close contact, including sexual contact. It was widely transmitted in eastern and central Africa. However, in cases identified in travellers outside the continent, spread has been very limited, according to the US Centers for Disease Control and Prevention.

More than 3,100 confirmed cases have been reported since late September, according to the World Health Organization. The vast majority of these cases have been in three African countries: Burundi, Uganda, and the Democratic Republic of the Congo.

Since then, cases of travellers with the new form of mpox have been reported in Germany, India, Kenya, Sweden, Thailand, Zimbabwe, and the United Kingdom.

Health officials said earlier this month that the situation in Congo appears to be stabilising. The Africa CDC has estimated that Congo needs at least 3 million mpox vaccines to stop the spread, and another 7 million vaccines are needed for the rest of Africa. The spread is primarily through sexual transmission, as well as close contact among children, pregnant women, and other vulnerable groups.

This current outbreak is different from the 2022 global outbreak of mpox, where gay and bisexual men made up the vast majority of cases.