(Bloomberg) -- China has detected the new mutated strain of the mpox virus for the first time, as the pathogen spreads to more geographies after the World Health Organization declared the outbreak in Africa a new global health emergency last year.
China’s Center for Disease Control and Prevention said on Thursday it has found a cluster of a new mpox strain, known as clade Ib, with the source being traced back to a foreign national who has traveled to and lived in the Democratic Republic of the Congo.
Another four cases have been found among people who had close contact with the source, said China’s CDC, without identifying the location of the outbreak. Authorities in Zhejiang, Guangdong, Beijing, Tianjin and other provinces have launched a joint prevention and control mechanism to carry out epidemic tracing, risk investigation, case diagnosis and treatment.
The patients’ symptoms are mild, including rashes and blisters, the CDC said. The patients and others who are at risk of infection are receiving medical treatment or are under observation.
The new strain has been spreading across several African countries, affecting mainly children and adolescents. Infections have spilled over from Africa to other continents, including Europe and North America.
The US reported its first case of clade I mpox in November, but reassured the public the risk remained “very low”. In Asia, the variant has also been detected in countries like Thailand and India.
Unlike an earlier milder strain that erupted in 2022 and spread primarily through men who have sex with men, the current variant is spreading through all kinds of sexual activity and other close physical contact.
Asian countries from China to Indian and Pakistan — many of which are densely populated — have beefed up surveillance of infections. Travelers from affected countries were being asked to self-report symptoms and hospitals were on alert for suspected cases.
After the WHO raised the alert levels on mpox, China has begun asking travelers from affected regions, those who have been in contact with mpox patients or individuals experiencing symptoms to self-report to customs officials upon entry, where they may undergo testing.
(Updated with additional information in first and sixth paragraphs.)
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