Johannesburg – A Colombian businessman, who is visiting South Africa, has been diagnosed with the Zika virus, Health Minister Aaron Motsoaledi said on Friday. “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."A case of sexual transmission was recently reported in the US but is still regarded as very rare."The businessman was diagnosed by a private Johannesburg pathology laboratory. The National Institute for Communicable Diseases is performing a confirmation test. Motsoaledi's spokesperson Joe Maila said the businessman presented with fever and a rash about four days after he arrived in the country but he is now fully recovered."The infection was acquired in Colombia prior to his visit to Johannesburg for business. Colombia is experiencing a large outbreak of the Zika virus."He said the virus is present in the blood of a patient for a very short time – typically less than seven days.A person carrying the virus in their blood will have to be bitten by a correct subtype of an Aedes aegypti mosquito within this time for the virus to be transmitted to the next person through a bite from the same mosquito."The Aedes mosquito that transmit the Zika virus in South America also transmit dengue fever and yellow fever, but these viruses are not found in South Africa, indicating that the local Aedes mosquito does not contribute to the spread of the Zika virus," Maila said. "Given the frequency of travel between South Africa and a number of countries currently experiencing outbreaks of the Zika virus, it is likely that other sporadic imported cases will be seen here in travellers as has been the experience in a number of countries."The World Health Organisation said the Zika virus is "spreading explosively" in the Americas and the region may see up to four million cases of the disease strongly suspected of causing birth defects.