The World Health Organization said "sustained transmission" of monkeypox worldwide could see the virus begin to move into high-risk groups, such as pregnant people, immunocompromised people and children.
WHO said on Wednesday it is investigating reports of infected children, including two cases in the United Kingdom, as well as following up reports in Spain and France. None of the cases in children have been severe.
The virus has now been identified in more than 50 new countries outside the countries in Africa where it is endemic. Cases are also rising in those countries, said WHO, calling for testing to be ramped up.