Suspected Rift Valley fever outbreak

An outbreak of Rift Valley fever (RVF), an animal disease that sometimes infects humans, appears to have spread from Kenya into southern Somalia. Of 100 suspected cases there have been 48 deaths. One case has been confirmed to have been RVF. Many of theses cases are in the Lower Juba region.

Patients - mostly nomadic herders - died in Doble, an area about 18 km north of the Kenyan border. Their diagnosis has not been confirmed due to insecurity in the region, but animals in the area have been spontaneously aborting. This is a key sign of RVF in livestock.

Due to ongoing fighting and a recent air strike, the area is considered highly insecure. The border between Kenya and Somalia is closed and, according to WHO, the situation is "not favourable for resumption of humanitarian relief".

In addition to the fighting, recent heavy rains and flooding make it impossible to assess the outbreak effectively.

RVF has killed 162 people in Kenya since mid-December. In late 1997, after exceptionally heavy rains, an epidemic of Rift Valley fever resulted in the deaths of at least 300 people and large numbers of animals in remote parts of north-eastern Kenya, southern Kenya, and southern Somalia.

The Disease Rift Valley fever (RVF) is a viral disease that usually infects domestic animals such as cattle, sheep, goats, buffalo and camels. The disease sometimes transfers to humans, usually causing a mild flu-like illness. However, in some cases the illness can be acute and deadly.

Humans can get the disease through the bite of an infected mosquito or other bloodsucking insect. They can also contract it via contact with the blood, organs, or bodily fluids of sick animals. This contact can occur during care giving, slaughtering, or handling infected meat for food preparation. The virus may enter through the skin or via inhalation.

People infected with RVF may react in many different ways. Some will not develop symptoms. Others will have a mild, flu-like illness with fever, weakness, muscle and back pain, and dizziness. Some patients also develop meningitis-like symptoms: neck stiffness, sensitivity to light (photophobia) and vomiting.

In severe cases, people may develop a hemorrhagic fever, which can cause severe liver disease, yellowing of the eyes and skin (jaundice), and signs of bleeding including blood in the feces and vomit, bleeding gums and visible rash caused by blood pools under the skin (purpuric rash). About 50% of those who develop hemorrhagic fever die.

Other severe effects include encephalitis, or brain inflammation, and eye disease. Both of these complications occur one to three weeks after symptoms first appear. Encephalitis can cause headache, seizure, coma or death. Eye inflammation and sores can result in permanent vision loss.

There is no established treatment for RVF. Most patients recover within two days to one week.

When in affected areas, avoid contact with raw meat and bodily fluids of potentially infected animals. As there is no vaccine available, preventing mosquito bites is critical to preventing Rift Valley fever.

Prevent mosquito bites Mosquitoes transmit many diseases that threaten travellers, and different mosquitoes bite at different times of the day. For example, the mosquitoes that spread malaria bite at night (from "dusk until dawn"), whereas the mosquitoes that spread dengue fever bite during the day.

Prevent bites while outdoors:

• · Wear light-Colored clothing that covers most of the body (long sleeves and long pants). 
• · Use insect repellent that contains DEET. Adults and children more than two months of age can use preparations containing up to 35% DEET - the higher the concentration, the longer it repels. Longer acting preparations are also available. Reapply after swimming or excessive sweating. Prevent bites while you are indoors or asleep:
• · Check that there is fly-wire on the windows. 
• · Use "knock-down" insect spray to kill mosquitoes in your room. 
• · Use mosquito coils or electric insecticide vaporizers if mosquitoes can get into your room. 
• · Note that air conditioning also repels mosquitoes. 
• · Consider using a bed net impregnated with a pyrethroid insecticide. Long-lasting pre-treated bed nets are available.