Covid patients infected with the new strain started appearing around November 18, Dr. Angelique Coetzee, chair of the South African Medical Association, told the BBC on Sunday. The first such patient, a man in his 30s, told her he was “extremely tired”for several days, and also referenced body aches and “a bit of headache,” she said.

The patient did not exhibit symptoms typically associated with Delta or any previous Covid-19 strain like a cough or loss of taste or smell, and had a “scratchy throat” rather than a sore one, the doctor added.

Coetzee said that her colleagues reported similar cases of patients infected with the Omicron strain, who all experienced what she called “extremely mild symptoms.” She also said that no Omicron-infected patient she is aware of had been admitted to a hospital.

Her observations were partly confirmed by Professor Barry Schoub, a virologist and the head of South Africa’s Ministerial Advisory Committee on Covid-19 vaccines. “So far, the cases have been pretty mild,” he told Sky News on Sunday. “We have a hospital surveillance program here as well and it has not shown any significant uptick [in hospitalizations],” he added.

All the Omicron cases recorded so far have been “mild to moderate,” Schoub said. However, he went on to warn that these are “the early days” and one has to wait and see to better understand the real danger posed by the new strain.

The professor also admitted that the virus spreads “very rapidly”and the number of reported Omicron cases in South Africa rose from just under 300 new cases a day to over 3,200 a day over some 10 days.

The Omicron variant first identified in southern Africa has since spread beyond the region, with cases in several European countries linked to travelers coming from South Africa. The strain’s discovery triggered a wave of international response measures including flight and travel restrictions.  Japan, Israel and Morocco barred all foreign travelers, and Australia delayed reopening its borders for two weeks.