Monkeypox, a viral disease that causes flu-like symptoms and skin lesions, is endemic in parts of Africa, but this year there has been an increase in cases both on the continent and in the rest of the world.
Africa has documented 1,597 suspected cases of the virus since the start of 2022, of which 66 have been fatal, according tothe continent's top public health agency, the Africa Centers for Disease Control and Prevention (CDC).
Moeti said eight African countries now had confirmed cases, including Nigeria, Cameroon and Democratic Republic of Congo where it is endemic, but also Benin and Ghana where the4 virus is not normally found.
"Although we're certainly not recommending mass vaccination at this stage, we must ensure that we are ready should the need arise," Moeti said at a weekly briefing.
Global stocks of smallpox jabs that offer protection against monkeypox are "extremely limited at this stage", she added, noting that the WHO was working to ensure fair access to vaccines and treatment.
The acting director of the Africa CDC, Ahmed Ogwell Ouma, warned against a repeat of the situation at the start of the global COVID-19 vaccination drive, when rich countries hoarded doses at the expense of poorer ones, especially in Africa.
"We should not have a situation like the COVID vaccines where we end up with Africa not having much," he told a separate media briefing.
"It is our position that when the smallpox vaccines are released to address monkeypox, it should start here in Africa, where the burden is larger, the risk higher and the geographical spread is also broader."
The WHO is due to convene an emergency committee next week to assess whether the monkeypox outbreak represents a public health emergency of international concern.