An increase in COVID-19 infections that has been reported in many African countries poses a threat to the continent's already fragile public health systems, a World Health Organization (WHO) official said on Thursday.

Matshidiso Moeti, WHO regional director for Africa, said the continent was on the verge of a new wave of coronavirus infections amid easing of containment measures, cold weather and stalled vaccination targeting high-risk groups.

"The threat of a third wave in Africa is real and rising. Our priority is clear. It is crucial that we swiftly get vaccines into the arms of Africans at high risk of falling seriously ill and dying of COVID-19," Moeti said in a statement.

She warned that heightened movement and arrival of winter could fuel a new wave of coronavirus infections in Africa, adding that governments should revamp critical care infrastructure to avert a high toll of fatalities.

According to WHO, Africa has recorded a 20 percent spike in COVID-19 positive cases in the last two weeks while eight countries have witnessed a 30 percent increase in their caseload in a week's period.

Moeti said the pandemic has been trending upwards in 14 African countries in the last week with Uganda registering a 131 percent week-on-week rise in cases in the past week, as infection clusters are reported in schools and among health workers.

She said that South Africa, Angola and Namibia have also experienced a resurgence in infections as they enter a cold season that is ideal for the spread of the virus.

Moeti said that stalled COVID-19 vaccination linked to global supply challenges could escalate surges in Africa, adding that the continent's health facilities should be revamped to cope with a spike in the number of critically ill patients.

"We must better equip our hospitals and medical staff to avert the worst effects of a runaway surge," Moeti said, adding that WHO has deployed experts to several African countries to boost clinical care of severely ill COVID-19 patients.