China’s Centre for Disease Control and Prevention said it had found a cluster outbreak of the Ib subclade that started with the infection a foreign national who has a history of travel and residence in the Democratic Republic of Congo (DRC).

Four further cases have been found in people infected after close contact with this person. The patients’ symptoms are mild and include skin rash and blisters.

Mpox spreads through close contact and causes flu-like symptoms and pus-filled lesions on the body. Although usually mild, it can be fatal in rare cases.

WHO last August declared mpox a global public health emergency for the second time in two years, following an outbreak in the DRC that spread to neighbouring countries.

The outbreak began with the spread of an endemic strain, known as clade I, but the clade Ib variant appears to spread more easily through routine close contact, including sexual contact.

The variant has spread to Burundi, Kenya, Rwanda and Uganda, triggering the emergency declaration from the WHO.

China said in August last year it would monitor people and goods entering the country for mpox.

The country’s national health commission said mpox would be managed as a Category B infectious disease, enabling officials to take emergency measures such as restricting gatherings, suspending work and school, and sealing off areas when there is an outbreak of a disease.