Health officials on the African continent are seeing a sharp rise in COVID-19 cases, with an 83% surge seen during the past week.

The surge is driven by both the Delta and the Omicron variants, according to World Health Organization (WHO) experts who provided an update Tuesday. They warn that with stubbornly low vaccination rates, more waves might be on the horizon. WHO predicts that the 70% vaccine coverage now achieved in some parts of the world will not happen until August 2024 for Africans.

Only 20 African countries had vaccinated at least 10% of their population.

The good news is that COVID infections are causing fewer deaths. WHO said fatalities within the first three weeks of the pandemic were just over 3,000. For the week ending December 12, there were more than 196,000 new cases. That was up from 107,000 in the previous week. Cases are now doubling every five days.

South Africa has seen a 66% rise in new cases in the past week but hospitalizations remain low. Those cases include President Cyril Ramaphosa, who is recovering from a mild case of COVID. Deaths remain low as well, but WHO warns the numbers can change.

“We are cautiously optimistic that deaths and severe illness will remain low in the current wave, but slow vaccine rollout in Africa means both will be much higher than they should be,” said WHO Africa director Dr. Matshidiso Moeti.

“We’ve known for quite some time now that new variants like Beta, Delta or Omicron could regularly emerge to spark new outbreaks globally, but vaccine-deprived regions like Africa will be especially vulnerable.”

WHO officials also said the travel bans targeting African nations continue to hamper efforts to protect the health of their citizens.

All told, there have been 8.9 million confirmed cases of COVID-19 in African nations.