Rift Valley Fever, a rare zoonotic viral disease, has claimed 155 lives in Kenya and caused huge losses of income in Kenya's pastoralist communities. The outbreak of the disease has exacerbated an already precarious food insecurity and livelihoods situation, following the massive floods in Kenya and neighbouring countries at the end of 2006. A large number of animals were lost to the disease.
While Rift Valley Fever is unfortunately familiar to farmers in Kenya, Tanzania and other countries in the region, not much is known about the virus causing the disease. It is transmitted primarily to humans through contact with infected animal matter such as blood or other fluids, as well as animal organs. Consumption of raw milk from an infected animal, an important element in the diet of many nomadic pastoralists in Kenya, is also thought to lead to infection. RVF is also spread by livestock through mosquito bites. The infected mosquito eggs are often laid around river banks and can stay dormant for years until they get submerged. The eggs then hatch to mosquitoes that spread the virus.
In Kenya, RVF has been well known for over 60 years. As early as 1913, a disease fitting the description of RVF was blamed for the loss of sheep in the Rift Valley in Kenya. So far, there is no cure and doctors are only able to treat the symptoms. About one per cent of people contracting RVF develop the disease in a severe form; approximately half of those die. The last large outbreak was in 1997, following heavy rains blamed on El Nino, when some 27,500 people were infected and 170 died in Garissa District.
This time around, the first case of RVF was reported in Gurufa, Garissa, on 7 December 2006. Almost simultaneously, outbreaks were reported in a number of other districts, including Ijara, Wajir, Tana River and Isiolo - all of which had suffered from the extensive flooding in Kenya's North Eastern Province.
Nearly 700 suspected cases of RVF were recorded in Kenya, according to the Ministry of Health, with 155 deaths. The worst affected districts were Garissa, Ijara and Wajir districts in North Eastern Province, Tana River and Kilifi districts in Coast Province, and Kirinyaga and Maragwa districts in Central Province.
The outbreak lead to a government-imposed ban on the slaughter of livestock in the affected areas, which led to the closure of key livestock markets, as well as a ban on movement and slaughter of animals. This accentuated the precarious situation of pastoralists' welfare particularly in North Eastern Province. The ban on the slaughter of animals has now been lifted in Garissa, Ijara, Mandera and Wajir districts of in North Eastern Province. However, the animal quarantine is in force awaiting review of veterinary department investigation.
At the peak of the RVF outbreak, the Kenya Red Cross Society was engaged in social mobilization activities, targeting health workers and the affected communities. Access to affected areas in Garissa posed the greatest challenge due to flooding in the area. With the assistance of Emergency Response Units (ERUs) from sister societies around the world and other partners, the Kenya Red Cross assisted in the establishment of Special Wards in Garissa Provincial Hospital and Ngao Sub-District Hospital in Garsen.
The ward in Ngao Sub-District Hospital was established with support from the Japanese and Australian Red Cross and MSF-Spain. The Kenya Red Cross also worked with the MoH to institute timely and effective care to suspected and/or confirmed RVF cases. The Medical ERUs helped to train medical personnel working in local health facilities on universal precautions, early case detection and referral.
Significant government vaccination campaigns targeting 1.5 million livestock (cattle, sheep and goats), as well as other preventive activity is ongoing in 33 districts where RVF cases have been reported. Other interventions include supportive case management; enhanced surveillance; community mobilization/public health education and veterinary intervention like the ban on slaughtering of animals currently in force in Marigat and Makutano parts of Baringo. Vector Control is also ongoing through the spraying of high risk animals with synthetic pyrethroid (SI).
According to the World Health Organization (WHO), RVF can be prevented by a sustained programme of animal vaccination. Live, attenuated and killed vaccines have been developed for veterinary use. The live vaccine requires only one dose and produces long-lived immunity, but the presently-available vaccine may cause abortion if given to pregnant animals. The killed vaccines do not cause these unwanted effects, but multiple doses must be given to produce protective immunity. This may prove problematic in endemic areas.
The available vaccine is only for use with livestock. In humans, an inactivated vaccine has been developed. This vaccine is not licensed and is not commercially available, but has been used experimentally to protect veterinary and laboratory personnel at high risk of exposure to RVF. Other candidate vaccines are under investigation.
In neighbouring Tanzania, the National Society has organized a one-day seminar on RVF in the capital city of Dodoma with participation of local authorities, Tanzania Red Cross volunteers and representatives of local townships and villages. Following the seminar the volunteers went back into villages to educate local communities on this epidemic.
A total of 90 people in Dodoma were infected and 19 of those lost their lives. The total number of RVF deaths in Tanzania now stands at 33. The majority of Dodoma residents are livestock keepers and the death of large number of livestock simply means dwindling of peoples economic resources, Mr Yunus Rugaiyamu, the Regional Administrative Secretary, lamented and added that "we must cooperate and work together in order to get rid of this killer disease in our region."
The number of Tanzanian regions with suspected cases of RVF has continued to rise - now standing at eight: Arusha, Manyara, Tanga, Kilimanjaro, Dodoma, Morogoro, Singida and Iringa. In Dar es Salaam, Regional Commissioner Mr. A Kandoro has announced a tentative ban on the sale of meat grilled at roadside stalls (kebabs) and urges the community to watch their eating manners as precautionary measure, while leading authorities asked to raise the level of alertness against its entry in the city.
Responding to the outbreaks, the Tanzania Red Cross has distributed 100 mosquito nets, 200 blankets and two tents through the Regional Medical Officer in Dodoma to be used at established treatment camps, while another 100 mosquito nets will be distributed by Dodoma Red Cross branch to RVF affected families. The Society also provided 4,000 leaflets to give health education to the local communities.