Another 23 positive cases were confirmed on Sunday, bringing the total number in South Africa to 61.
Of these cases, according to President Cyril Ramaphosa, was the country's first local transmission.
Prior to the president's announcement, all cases had involved people who travelled to South Africa from overseas.
President Cyril Ramaphosa has declared a national state of disaster as the number of confirmed Covid-19 cases increased from 51 to 61 on Sunday night.
Ramaphosa also announced several response measures to limit the spread of the novel coronavirus, which has been declared a pandemic by the World Health Organization (WHO).
The president, addressing the nation after a special Cabinet meeting, added that the number of cases is expected to increase in the coming days.
President Cyril Ramaphosa on Sunday said he was worried about the first confirmed local transmission of coronavirus in the country.
In his address to the nation, the president also confirmed that total number of confirmed cases in the country were now at 61.
"Initially, it was people who had travelled out of the country, especially from Italy, who had positively tested for the virus.
"It is concerning that we are now dealing with internal transmission of the virus", he said.
The Covid-19 outbreak cause by the novel coronavirus, officially named SARS-CoV-2, has been declared a national emergency, President Cyril Ramaphosa announced on Sunday.
Measures to stop the spread of the virus in South Africa include the partial closure of borders, banning visits to prisons, closing schools, and prohibiting events that involve the gathering of more than 100 people.
Those measures can be enforced using legislation that gives the government wide-ranging powers to deal with disasters, including mobilising government resources without paperwork and banning alcohol.
Coronavirus in SA: President says first local transmission is concerning
Wits University and the University of Cape Town have suspended classes in order to limit the spread of the coronavirus, the institutions announced on Sunday.
This came shortly after President Cyril Ramaphosa declared a national state of disaster on Sunday as the Covid-19 crisis worsens around the world.
UCT took a decision to break immediately for the term 1 vacation and suspend classes from Monday, vice-chancellor Professor Mamokgethi Phakeng said in a statement.
"We were persuaded of the importance of this step as a precautionary, proactive measure to minimise the risk of spreading coronavirus disease 2019," Phakeng said.
WHAT'S HAPPENING IN THE REST OF THE WORLD
For the latest global data, follow this interactive map from Johns Hopkins University & Medicine.
Positive cases worldwide are now close to 170 000, while deaths are now more than 6 500.
The spread in Italy has been dramatic, with now nearly 25 000 cases, and more than 1 800
People aged over 70 in Britain will be asked to stay in strict isolation at home or in care homes for up to 4 months under a radical new plan to prevent them from catching the coronavirus.
Asked to confirm an ITV report of the proposal, Health Secretary Matt Hancock said on Sunday: "That is in the action plan, yes."
"And we will be setting it out with more detail when it is the right time to do so because we absolutely appreciate that it is a very big ask of the elderly and the vulnerable, and it's for their own self-protection."
Hancock said the plan was a "very big ask" for older people, but said it was a measure for their own protection, and confirmed it would be introduced in the "coming weeks."
HEALTH TIPS (as recommended by the NICD and WHO)
• Avoid contact with people who have respiratory infections
• Maintain social distancing – stay at least one metre away from somebody who is coughing or sneezing
• Practise frequent hand-washing, especially after direct contact with ill people or their environment
• Avoid touching your eyes, nose and mouth, as your hands touch many surfaces and could potentially transfer the virus
• Practise respiratory hygiene – cover your mouth with your bent elbow or tissue when you cough or sneeze. Remember to dispose the tissue immediately after use.
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