Indonesian doctor Cheras Sjarfi says the small public hospital where she works in south Jakarta was not ready for the influx of Covid-19 patients who arrived after a surge of new infections in the world's fourth most populous country, Reuters reports.

Only equipped for basic health care, her facility has had to treat Covid-19 patients even though it lacks the life-saving ventilators and intensive care units they sometimes require.

"We weren't prepared for this situation," she said, adding that the situation at smaller hospitals like hers showed how severe things had become.

She is working 12-hour shifts, double the normal length, after she said some of her colleagues were infected despite being fully vaccinated.

Still, despite the huge strain and concerns that she could be re-infected with Covid-19, Cheras tries to remains positive. "Although we are exhausted and wonder when will this end ... I think it still manageable," she said.