Humans can contract the disease by eating meat from infected animals or by handling sick livestock. Favorable weather conditions in the countries of the Horn of Africa have put the risk of infection by the Rift Valley fever virus for both humans and animals at minimal to negligible, reported the World Health Organization and the United Nations Food and Agriculture Organization March 5. In fact, the high rate of infection during that time has made many livestock animals immune to the virus and is contributing to the low risk of infection at this time, the agencies report. Remote sensing satellite data of climatic conditions fully support ground observations that conditions in the Horn of Africa countries are highly unfavorable for multiplication of mosquito vectors of the Rift Valley fever virus. The Rift Valley fever virus is spread primarily by mosquitoes and mainly affects livestock.
Humans can contract the disease by eating meat from infected animals or by handling sick livestock.
The disease causes a fever, which is sometimes complicated by hemorrhage, inflammation of the brain and blindness. Humans can protect themselves through the use of vaccines, however the infrastructure to distribute the vaccine is limited in impoverished regions of the world. Outbreaks can best be maintained by spraying the mosquito breeding grounds, dambos, with the hormone Methoprene which prevents mosquito larvae from becoming adults. The low risk of infection in the Horn of Africa countries has also prompted the World Health Organization and the Food and Agriculture Organization to announce that livestock exports from that region of the world are safe. The World Health Organization has also relaxed health warnings to travelers in the Rift Valley to normal following special precautions that were issued in late 1997.