PRETORIA– The South African Department of Agriculture, Forestry and Fisheries says a case of Rift Valley Fever, an acute, fever-causing viral disease most commonly affecting domesticated animals such as cattle, has been confirmed at one farm in the Jacobsdal area of Free State Province.

So far, it is the only farm reported to be affected and further investigations are being carried out by the local veterinary services. Rift Valley Fever is caused by a virus carried by mosquitoes. It affects cattle, sheep and goats and causes abortions and deaths in especially young animals.

Humans can be infected with the fever if they come into contact with the blood and other body fluids of an infected animal or an aborted foetus.

Care should be taken when handling possibly infected animals or carcasses of animals that have died of the disease. Symptoms in humans are flu-like and some individuals can develop more serious complications. If a person suspects that they might have been infected with Rift Valley Fever, they must consult a doctor, the department said in a statement Thursday.

According to the department, the re-occurrence of Rift Valley Fever is caused by increased rainfall, which in turn causes an increase in the population of mosquitoes.

As this outbreak occurred in the beginning of the (Southern hemisphere) winter season, it will probably be an isolated incident as the cold weather will result in a decrease in the number of mosquitoes and therefore decrease the risk of the disease spreading,” the department said.

It must be noted that the risk will increase at the start of the summer season. This outbreak provides us with a useful warning that all cattle, sheep and goats have to be vaccinated to ensure that the level of immunity in the herds is high when the next summer season starts and the risk increases.”

Farmers are advised to vaccinate their animals against Rift Valley Fever. Live vaccines can only be used in non-pregnant animals as the live vaccine can cause abortions.