JOHANNESBURG -- South Africa's resurgence of COVID-19 is setting record numbers of new daily cases, centered in Johannesburg and driven by the delta variant, health officials said Sunday.

More than 26,000 new cases were reported on Saturday, up from 24,000 the previous day, according to the National Institute for Communicable Diseases, surpassing the highest number of new cases in previous waves and quickly bringing many hospitals to capacity. More than 13,800 COVID-19 patients are currently in South African hospitals where some facilities are canceling elective surgeries to free up beds and health care workers.

South Africa's official death toll has risen above 63,000, although statistics on excess deaths suggest the country's actual number of virus fatalities may be more than 170,000.

South Africa's 2 million cases account for more than 30% of the cases reported by Africa's 54 countries, according to the Africa Centers for Disease Control and Prevention.

President Cyril Ramaphosa last week increased restrictions to try to reduce the spread of the virus, including extending a nighttime curfew, banning the sale of alcohol, closing many schools and stopping travel into and out of Gauteng, the country's most populous province that includes Johannesburg and the capital, Pretoria. Gauteng accounts for more than 60% of the new cases and officials fear other provinces and cities will soon follow.

After a slow start, South Africa's vaccination drive is picking up pace but is still far behind developed nations. To date, more than 3.3 million of South Africa's 60 million people have received at least one jab of the Pfizer or Johnson & Johnson vaccines. The inoculation campaign started with health care workers, those aged 60 and over and schoolteachers. On Monday police can get a jab and soon those 50 and over can too.

The nation's Health Products Regulatory Authority on Saturday authorized the vaccine manufactured by China's Sinovac, providing that it submits final results of ongoing clinical studies.

Neighbouring southern African countries including Mozambique, Namibia, Zambia and Zimbabwe are also struggling to cope with a surge of infections.