Tropical diseases

1. Tropical diseases Prepared by : Abobakr haj alshaikh Superved by :prof M.A.abuhif

2. The tropical diseases are disease that are prevalent or unique in to tropical an subtropical regions. • Insects and Ticks are the most common diseases carrier or vector .

3. Effect of trashumance • Used to describe the seasonal movement of livestock to regions of different climates. • Is a highly specialized mode of life to permits the utilization land witch are seasonally productive. • Start between summer and winter ,or dry to wet season

4. Transhumant peoples own most of livestock in many country (Libya, Nigeria, Sudan, Syria) • In south American and African country they are important contributors to their economic countries. • They are maintain a rang of different livestock species (sheep, goats, cattle, buffalo, camel..)

5. Factors determining distribution 1- close association between people, their animal, and their environmental (complex interaction). 2- lack of piped water and sanitation absence of permanent housing . 3- lack diseases control programmes , veterinary and educational facilities (Macpherson, 1994).

6. Climate • Extremes of temperature, above 40₀c and below 10₀c and low relative humidity are inimical to the survival or maturation of parasite • All parasite have optimum temperature at witch mature and play role in limiting their geographical distribution • Larval stage of nematode species, may develop inside protective eggs may survive for long period

7. Long enough to be available for transmission the following season when the transhumance group again pass through the area . • In the arid areas L4 of larvae of Haemonchus spp. accumulate in the cattle at the end of rainy season persist in this form over the long dry season and then maturation in next rainy season

8. Droughts • Seasonal and prolonged droughts result in change in nutrition and survival of livestock can effect the epidemiology of diseases . • The prolonged drought in Turkana between 1978and 1981 killed over 70% of the livestock an led to heavy E.granulosus infection in dogs (Wachira et al., 1990)

9. Impact of parasitic diseases • The build – up of faecally transmitted infections and arthropods well be influence by 1- the sized of the community 2- the time spent in one location 3- environmental condition Parasitic infections have profound influence on the migration patterns (Fulani ,Bagara)

10. Zoonotic parasitic • Infections are much greater in transhumant group for the 1- poor sanitary contamination 2- sharing water sources 3- relationship with domestic animal (dogs –women and children )

11. Nematodes larval require period of environmental maturation before becoming infective this may be only a few hours or weak to month • Temperature play an important role in the time taken for maturation (Trichuris spp.50 days in18-15 and 10days in 30c ) • Migration may serve introduce parasites in to new areas

12. Domestic - wild life interaction • Migration may bring animal in to contact wail animal • Contact facilitate exchange of many diseases (rinderpest ,bluetongue ,trypansomosis theileriosis) • Rabbits and hares act as reservoir host

13. Husbandry practices • The transhumant grazing young and old animal of different species together well favour the control of some helminth but also facilitates the transmission