South Korea has reported more than 100 new coronavirus cases for the first time in four months, while South Africa also announced a surge in infections and some US states tightened anti-disease controls.

The 113 new cases in South Korea include 36 workers returning from Iraq and 32 crew members of a Russian freighter, the government said.

Authorities had previously warned to expect a spike in cases from abroad and appealed to the public not to be alarmed.

South Africa, Africa’s hardest-hit country, reported more than 13,104 new confirmed cases, raising its total to 408,052. The government has reported 6,093 deaths.

Coronavirus testing
Several countries have seen a spike in coronavirus cases (Rebecca Blackwell/AP)

President Cyril Ramaphosa said on Thursday that schools will “take a break” for a month to protect children.

But despite rising infections, restaurant and hospitality workers have staged protested this week to demand a loosening of restrictions on their industries.

China, which has relaxed most of its anti-virus controls after case numbers dropped off, reported 34 new infections – including 29 that were contracted within the country.

More than 640,000 deaths and 15.7 million cases have now been reported worldwide, according to data compiled by Johns Hopkins University.

Global cases of coronavirus
(PA Graphics)

India, the country with the third-highest infection total behind the United States and Brazil, reported its death toll rose by 740 in the last 24 hours to take the total to 30,601.

The government also reported a surge of nearly 49,000 new cases, raising its total to over 1.2 million.

The All India Institute of Medical Sciences, a premier teaching hospital in the capital of New Delhi, said it administered the first dose of a trial Covid-19 vaccine on Friday.

Covaxin is among nearly two dozen candidate vaccines that are in human trials around the world.

In Brazil, president Jair Bolsonaro said he has now tested negative for the virus, based on a fourth test since he said on July 7 that he had Covid-19.

The 65-year-old leader tested positive for the third time on Wednesday.

Now that Mr Bolsonaro is clear of the virus, he is expected to return to mingling in crowds as he used to do before his diagnosis.

In the United States, governor Tate Reeves of Mississippi tightened controls on bars to protect “young, drunk, careless folks”. Bars were already limited to operating at 50% capacity and they will now also have to ensure all patrons are seated and stop sales at 11pm.

New Orleans cafe
New Orleans bars have been told in increase restrictions in a bid to stem the spread of coronavirus (Gerald Herbert/AP)

Mayor LaToya Cantrell of New Orleans ordered bars to close and banned restaurants from selling alcoholic drinks to take away. That came after more than 2,000 new cases were reported for the surrounding state of Louisiana, including 103 in New Orleans.

Arizona reported 89 additional deaths, raising the state’s fatality total to 3,142. The state reported 3,349 new cases, raising its total to 156,301.

The United States has suffered 145,391 deaths and has 4.1 million confirmed cases.

In Australia, premier Daniel Andrews of the southern state of Victoria announced five deaths and 357 new cases. Victoria, where the death toll has risen to 61, earlier closed its border with neighbouring New South Wales.

In Yemen, 97 medical workers have died of the virus, a serious blow to a country with few doctors that is in the midst of a five-year-old war.

Humanitarian group MedGlobal said in a report that the “overwhelming death toll” will have “immense short-term and long-term health effects”.