The number of confirmed Covid-19 infections in South Africa has risen to 150, president Cyril Ramaphosa announced on Thursday.

"The level of infection has now risen to 150 and that is concerning for us, because that already tells us that if you extrapolate that, it could start rising in greater numbers, which then reinforces our message about social distancing," Ramaphosa said.

This means that the number of known infections has increased by 34 since Tuesday. According to the government, 4 832 people have been tested so far.

Ramaphosa urged all South Africans, government officials included, to abide by regulations barring people from gathering in groups of more than 100 to curb the spread of the virus.

He was addressing the media after meeting with religious leaders, following suggestions that some religious groupings would defy the ban on large gatherings. Ramaphosa stressed that nobody would be exempted from the ban and thanked those who had agreed to fall in line.

Muslim organisations have cancelled Friday prayers and the Dutch Reformed Church and the Methodist Church, amongst others, have said they would respect the regulations.

"We are emboldened to carry on the work we are doing because we are supported by the churches," the president said.

Ramaphosa on Sunday declared the outbreak of the disease in South Africa a national disaster and government on Wednesday issued additional regulations, including restrictions on the alcohol trade, in a bid to contain the infection rate.

The department of health has voiced concern over the increasing number of local transmissions, two weeks after the country reported its first case of Covid-19.

The early cases were all people who had returned from high incidence countries abroad.

On Thursday morning, the University of Cape Town confirmed that a second member of its staff had tested positive for the virus, and said the infection was transmitted through contact with the first staff member who contracted Covid-19.