A public health emergency has been declared by the World Health Organisation over a new outbreak of mpox in several African nations, with at least three cases now reported outside of the continent.

Formerly known as monkeypox, the infection has been on the rise in the Democratic Republic of Congo, which accounts for 96 per cent of all cases in Africa.

More than 17,000 cases have now been confirmed across the continent, with the WHO saying the outbreak is of “international concern”.

The public health emergency was declared by the group’s director general, Dr Tedros Adhanom Ghebreyesus.

The outbreak comes as a new strain is identified, named clade 1, said to be spreading mainly through sexual networks. WHO says it has been identified in Burundi, Kenya, Rwanda and Uganda – all countries that have never reported cases of mpox before.

One case of this new strain has now been detected in Sweden, the country’s public health agency has confirmed. They say the person, who is now in isolation, had contracted it during a stay in an African country where other cases have been reported.