The World Health Organization (WHO) has said there is as yet no evidence that the spread of coronavirus is reduced in Africa because of the higher temperatures there.
The virus has so far multiplied more slowly in Africa than in Asia or Europe, but 34 African countries have now reported a total of more than 600 cases.
Health experts have stressed the need to prepare for a significant spike in infections.
The head of the Africa Centres for Disease Control and Prevention, John Nkengasong, warned that flight and other travel restrictions would help delay the virus - but would ultimately fail to contain it.