Jan 31 2007
Kenya is facing a possible national disaster over an outbreak of Rift Valley Fever (RVF).
Despite attempts by the government to control the spread of the disease and their assurances that there is no cause for alarm, 120 people have already died and there have been 400 reported cases of infection.
Nairobi along with 10 other districts are now declared to be high-risk areas, and at least 9 other districts are affected.
RVF is a disease which primarily affects animals, but occasionally causes disease in humans.
It can be severe in both animals and humans and lead to epidemics in both cases.
The RVF virus is spread amongst many types of animals by the bite of infected mosquitoes and a wide variety of mosquito species may act as the vector for transmission of the virus.
People may become infected with RVF either by being bitten by infected mosquitoes, or through contact with the blood, other body fluids or organs of infected animals, possibly during the care or slaughtering of infected animals, or possibly by drinking untreated milk.
The virus may infect humans through a break or wound in the skin, or through inhalation.
In humans the virus causes a flu-like illness, with fever, headache, muscle pain and backache.
Some patients also develop neck stiffness, and find exposure to light uncomfortable and experience vomiting; in these patients the disease, in the early stages, can often be mistaken for meningitis.
Most human cases are mild but a small proportion of patients develop a much more severe disease which appears as eye disease, or meningoencephalitis (inflammation of the brain and surrounding tissue) or haemorrhagic fever.
The result can be in some cases permanent visual loss, but for patients developing haemorrhagic disease the death rate is high and it is in these cases that most fatalities occur.
RVF can be prevented by a sustained program of animal vaccination and the use of appropriate protective clothing and care when handling sick animals or their tissues.
Other approaches to the control of disease involve protection from and control of the mosquito vectors.
The death of RVF-infected livestock often leads to substantial economic losses and it is this which poses such a threat to Kenya.
Many feel the government have underestimated the disease and was initially slow to implement measures to control the spread of the virus.
Veterinary experts say a buffer zone should have stopped the disease from spreading from North-Eastern Province where it was first reported and they say of two million livestock targeted for vaccination, only 400,000 have received shots.
The government has promised that one million doses of the vaccines will be distributed to the high-risk districts, has banned animal slaughter in the affected regions and quarantined animals.
Vulnerable animals and mosquito breeding grounds have also been sprayed.
Experts say the public education programme must intensified so people understand what needs to be done to protect themselves and their livestock, and that regardless of social and cultural rites, some animals must be culled to halt the spread of the virus.
An earlier outbreak of RVF in Kenya in 1997-1998 killed hundreds of people.