The businessman who visited Johannesburg has been diagnosed with Zika by a private Johannesburg pathology laboratory, Health Minister Aaron Motsoaledi said.

At the moment the SA National Institute for Communicable Diseases (NICD) is busy conducting confirmatory tests, according to the minister.

The businessman was in SA for four days when he went to see his doctor because of fever and rash, but now he is fully recovered, Motsoaledi said.

"This infection was acquired in Colombia before he visited Johannesburg," said Motsoaledi.

"The confirmation of this particular case poses no risk to the South African population as the virus is not transmitted from human to human but through the Aedes aegypti mosquito and or possibly from mother to the foetus in pregnant women," Motsoaledi said.

The virus is causing international alarm after spreading quickly in South and Central America and the Caribbean, with Brazil the worst affected country.

The World Health Organization declared an international health emergency on Feb. 1 over the virus, citing concern over a possible link with a rise in cases of microcephaly, a birth defect characterized by an abnormally small head that can result in developmental problems.