KENYA COUNTRY REPORT

Otindo, T. A.

Ag. Director,
Department of Veterinary Services,
Veterinary Research Laborataries
P. O. Box 00625,
KANGEMI,
NAIROBI, Kenya.

Introduction

            Kenya has an area of 575,000km2 :  The economy relies heavily on agricultural sector with about 38% of agricultural output coming from livestock.  The cattle population is estimated to be about 13 million comprising of 10 million beef and 3 million dairy herd.  The herd is concentrated in high potential areas.  In addition to cattle there are approximately 8 million sheep, 10.5 million goats, 200,000 pigs, 600,000 camels, 700,000 donkeys and about 22 million poultry.  Improvement and expansion of livestock industry is greatly hindered by vector borne diseases mainly tick borne and tsetse transmitted disease.  The Kenya Government has continued to lay a lot of emphasis on these two vector borne diseases.  Currently tsetse control is one of the core functions of the Ministry of Livestock and Fisheries Development.

1. Tsetse Distribution

In Kenya tsetse flies are found from sea level to an altitude of nearly 2000m above level.  The three tsetse fly groups are represented by 8 species of tsetse flies as follows:-

2.1.        Morsitans group
             Glossina pallidipes
             Glossina morsitans
             Glossina swynnertoni
             Glossina austeni

2.2       Fusca Group
            Glossina longipennis
            Glossina brevipalpis
            Glossina fuscipleuris

2.3.      Palpalis Group
            Glossina fuscipes fuscipes

            The above 8 species occur in 6 widely separated fly belts traversing various parts of the country (see Map 1).  G. pallidipes is the most widely distributed tsetse species in Kenya and is found in all the 6 major tsetse belts.  G. fuscipes fuscipes is confined to the Lake Victoria Basin in Western Kenya where it occurs along the Lake shore riverine thickets and peridomestic thickets.

            Glossina swynnertoni and G. fuscipleuris are confined to Narok-Kajiado fly belts which occur in the South Western part of Kenya and extends into Tanzania. G. austeni is only found in the Coastal belt.  G. longipennis and G. brevipalpis are confined to drier parts of the hinterland and forest relics respectively.  G. morsitans submorsitans occur in a small isolated tsetse belt along the Kenya/Uganda border.

3.         Tsetse and Trypanosomosis Problem

3.1.      About two thirds of Kenya comprising 7 out of 8 administrative provinces and 60% of productive, well watered rangelands are tsetse infested.  Some of the high potential areas including Coast, Western and Nyanza provinces have serious tsetse and trypanosomosis problems. These are areas that rely mainly on draught/oxen power for land tillage.  Lack of draught power as a result of trypanosomosis has led to low acreage under crops thereby enhancing poverty amongst the communities of the tsetse-infested region.

3.2.      The impact of tsetse problem is the economic loss arising from reduced livestock productivity and reduced animal draught power.  Trypanosomosis more often than not occurs in combination with other diseases. Chronic trypanosomosis predisposes affected animals to other infections and this is responsible for huge economic losses in terms of high mortality, low body weight and high sterility.  Economic loss to the country is estimated at Kshs.700m annually from livestock deaths. The cost of importation of trypanocidal drugs and pesticides amounts to kshs.300 million and Kshs.60 million respectively.

Tsetse-trypanosomosis infections:

Source: ILRI and KARI/TRC

4.1       Animal Trypanosomosis

            The major pathogenic trypanosomes in Kenya are Trypanosoma Congolense, T.vivax, T.simiae and T.evansi.  Cattle have been found to be reservoir hosts of T.brucei rhodensiense in sleeping sickness endemic areas in Nyanza and Western provinces of Kenya.

Cattle trypanosomosis is widespread in Kenya and occurs both within the tsetse belts, where it is transmitted by tsetse flies and outside tsetse belts where it is transmitted by biting flies. Camel trypanosomosis in Northern Kenya (T.evansi) is transmitted by biting flies. Trypanosomosis remains the major constraint affecting livestock production and productivity in pastoral areas thus drastically affecting poverty alleviation of pastoral communities in Kenya.

4.2       Human Trypanosomosis

            Over the past fifty years the number of reported cases of sleeping sickness in Kenya has never exceeded 500 a year, and since 1968 there have been less than 100 cases reported each year.  Sleeping sickness is caused by Trypanosoma brucei rhodesiense which is endemic in Lake Victoria basin since the first case was reported in 1902.

            Last detected cases were in Busia and Teso  Districts in 2002.  KARI/TRC continues with both active and passive surveillance to ensure the current status in sustained.

            Human trypanosomosis caused by Trypanosoma brucei rhodesiense is endemic in Lake Victoria Basin.  Human trypaosomosis does not occur anywhere else in Kenya.  There are two foci of human sleeping sickness in Kenya namely:-

1. Siaya, Busia, Teso and Bungoma foci to the North of lake Victoria Basin.
2. Lambwe Valley foci to the South of lake Victoria Basin.

5.  Country Activities

            Veterinary Department in the Ministry of Livestock and Fisheries is responsible for tsetse control in the country.  KARI/Trypanosomosis Research Centre is the National Research Institute mandated to carry out research on tsetse and trypanosomosis.  International Livestock Research Institute (ILRI) and International Centre For Insect Physiology and Ecology (ICIPE) are International Institutions which collaborate closely with national programmes.  The following activities are on-going:-

5.1       Routine tsetse surveys country-wide especially in lake Victoria Basin where intensive tsetse          surveys and control is a continuous process in order to deal with both human and livestock      trypanosomosis problem. This region is a priority area due to the occurrence of trypanosome    species that causes sleeping sickness in man.

5.2       Spot tsetse and trypanosomosis surveys as requested by farmers.

5.3       Tsetse control activities in all areas reported to have high incidences of livestock   trypanosomosis in tsetse infested areas.  Integrated approach is being carried out using odour-baited insecticide impregnated traps and targets and use of pour-ons on livestock which act as mobile targets.  Care is being taken to ensure drug resistance by ticks does not occur where pour-ons are in use.

5.4       Community education in order to prepare farmers to participate in all aspects of tsetse control activities.  The Government has realized that lack of involvement of beneficiaries has contributed very much to lack of sustainability of control programmes

5.5       Community education in proper drug use and administration in view of the fact that man    pastoralists have been found to be treating their animals due to inadequacy of field veterinary staff country-wide

5.6       Liasing with relevant Research Institutions both National and International to develop cheap technologies for tsetse control.  Such institutions as Universities, KARI/Kenya   Trypanosomosis Research Centre.  International Centre for Insect Physiology and Ecology (ICIPE) have been collaborating very much during national tsetse control programme implementation.

5.7       Seeking more collaboration with NGO’s to involve their participation in National tsetse control programme.

5.8       Offering technical advice to many large-scale livestock farmers who have now shown interest      favoured by many farmers due to escalating prices of trypanocides.

5.9       Supporting existing community based tsetse control programmes countrywide by giving them the necessary training.

5.10     Training and capacity building of staff

            Inspite of all these activities the fight against the tsetse menace remains since large chunks of the range lands is still unclaimed from the tsetse infestation. Due to shared tsetse belts, with neighbouring countries, a regional approach is necessary since tsetse flies know no country boundaries.

6.         Tsetse And Trypanosomosis Control Methods In Kenya

6.1.      Tsetse Control Methods

            Due to the presence of 8 species of tsetse flies, occupying different habitats various control methods are used in Kenya as follows.

6.1.1.Use of Odour baited insecticide Impregnated Traps

            Traps impregnated with deltamethrin and baited with acetone and cow urine are in use.  The most commonly used traps are NGU, Siamese and pyramidal traps depending on the species being dealt with.  Biconical traps are used for tsetse monitoring only.

6.1.2. Use of Synthetic Pyrethroids (Pour-ons)

            Synthetic pyrethroids are used either as pour ons or dip formulation on cattle which act as mobile targets from where tsetse pick the killer insecticide as cattle graze in the tsetse infested vegetation.  In this case cattle act as mobile targets.  This method is becoming popular in large-scale ranches in Kenya.

6.1.3.Oduor baited Insecticide treated Targets

            Targets made from cotton material are impregnated with synthetic Pyrethroids.  Deltamethrin 20% S.C. is commonly used for impregnating targets which are placed in the tsetse infested habitats.  The tsetse flies pick the killer insecticide from the targets.  Targets technology is being applied in big ranches in Kenya with good results.  They have also been used in Lambwe Valley as a barrier to stop tsetse flies from invading settlements around the valley and also suppress tsetse population inside the valley in readiness for tsetse eradication using S.I.T. method.

6.1.4.Ground Spraying

            Ground spraying using environmentally friendly synthetic pyrethroid Cypermethrin has been used in the past to suppress fly population. In Glossina fiscipes fuscipes infested areas of Western Kenya during sleeping sickness outbreaks.  However due to environmental concern ground spraying is being phased out in preference to other environmentally friendly control methods such as traps, targets and pour-ons.

6.1.5. Sterile Insect Technique (S.I.T.) Method

            S.I.T. has not been applied to control tsetse in Kenya.  However plans are under way to apply S.I.T. in Western Kenya to eradicate G.pallidipes in Lambwe Valley in the near future.  Mass rearing of G.pallidipes is going at KARI/Trypanosomosis Centre in readiness for mass release in Lambwe Valley by June 2006.

6.1.6.    Selective Bush Clearing

            Selective bush clearing is done in G.fuscipes fuscipes infested lake-shore, Riverine and peridomestic thickets in Western Kenya to minimize man/fly contact in sleeping sickness endemic areas to reduce chances of human contracting sleeping sickness.  Care is normally taken to ensure that only undesirable thickets are cleared.  This is followed by planting of high canopy trees of economic importance as fodder trees or for firewood.

6.1.7.    Communal spraying of Livestock in Crush pens and cattle  dips using synthetic pyrethroids

6.2.      Trypanosomosis Control Methods

6.2.1.Tsetse Control

            Tsetse control to reduces man/fly, livestock/fly contact thus protecting man and his livestock from contracting trypanosomosis.

6.2.2     Chemotherapy and Chemopropylaxis

            Use of trypanocidals for control of trypanosomosis is a common practice by the Kenyan pastoralists.  These trypanocidals are used to cure the sick animals and to protect the healthy ones from contracting trypanosomosis.

            Drug resistance has been reported in some places in the country posing a great danger to future management of trypanosomosis in Kenya.  The revalence of chemoresistance to trypanosomes is being studied in order to lay strategies to deal with such resistance.  The Kenya Government is carrying out intensive training of farmers on proper use of trypanocidals in order to reduce development of chemoresistance.

6.2.3     Grazing patterns

            Pastoralists in arid and semi arid tsetse infested areas avoid grazing their livestock in tsetse infested forest thus reducing livestock/tsetse contact.

            This reduces chances of livestock contracting trypanosomosis.

6.2.4.   Human Sleeping Sick Surveillance     

            Both active and passive human sleeping sickness surveillance is carried out in sleeping sickness endemic areas in Western Kenya especially the Kenya/Uganda border districts.  Positive cases are treated at Alupe sleeping sickness Hospital in Busia, Kenya.

7.         Human Trypanosomosis

            Human trypanosomosis caused by Trypanosoma brucei rhodesiense is endemic in Lake Victoria Basin.  Human trypanosomosis does not occur anywhere else in Kenya.  There are two foci of human sleeping sickness in Kenya namely:- Siaya, Busia, Teso and Bungoma foci to the North of lake Victoria Basin. And Lambwe Valley foci to the South of Lake Victoria Basin

            No case of sleeping sickness has been reported in Lambwe Valley focus since 1990.  However, in Busia, Teso and Bungoma sporadic cases have continued to be reported.  Confirmed cases are treated at Alupe Sleeping sickness Hospital.  No major outbreak of sleeping sickness has occurred in Kenya in the recent past due to concerted efforts by the Kenyan Government to maintain constant tsetse surveys and control along the Kenya/Uganda border.  It is worth noting that cattle in sleeping sickness endemic areas of Busia, Teso and Bungoma have been found to act as reservoir hosts for T.b. rhodesiense.

8.         Achievements

            Although total eradication of the tsetse flies in Kenya has not been achieved the following achievements have been made:-

8.1       Sleeping sickness in Lambwe Valley has been contained.  No case of Sleeping sickness has been reported in Lambwe Valley since 1990.  Ruma National Park in Lambwe Valley is now open for tourism exploitation.

8.2       Sleeping sickness in Siaya, Busia, Teso and Bungoma has been contained.  No major outbreak of sleeping sickness in these areas has been reported in the recent past.  The few cases reported in Busia, Teso and Bungoma are dealt with at Alupe Hospital where patients are treated.

8.3       No major cattle trypanosomosis outbreak has been reported in Nyanza and Western Provinces in the recent past since tsetse density has been reduced to a level where they can co-exist with livestock. The few cases of trypanosomosis found, are treated using trypanocidal drugs.

8.4       Due to decreasing tsetse problems in Nyanza and Western Provinces, the tsetse programme has been expanding to other provinces.  Rift Valley, Cental, Eastern, North Eastern and Coast Provinces have on-going tsetse control programmes in high priority areas.        

9.         Future Challenges

9.1       To reclaim all tsetse infested lands country for agricultural exploitation

9.2       To put in place appropriate land use practices that will ensure that there is minimum environmental degradation in addition to reducing chances of re-infestation by the tsetse flies of the lands reclaimed from tsetse infestation.

9.3       To put in place measures which will deal with possible re-infestation of our country by tsetse from neighbouring countries since tsetse flies know no boundaries.

9.4       To develop cheap, environmentally friendly and easily adaptable tsetse control methodologies

9.5       To empower the beneficiaries (rural communities) to be able to carry out tsetse control methods at village level by creating proper awareness and training in all aspects of the tsetse menace and adoption of the emerging tsetse control technologies.

9.6       To eradicate tsetse from our vast Game Parks which remain the major source of tsetse to the neighbouring settlement schemes.

10        PATTEC And Future Plans

            The Department strategy in the control of tsetse and trypanosomosis is focused on Area wide tsetse eradication.

            The initial phase of the strategy is to focus on

The department staff will continue with the control and suppression activities in the other belts.