THE CURRENT EPIDEMIOLOGY AND CONTROL OF TRYPANOSOMIASIS AND OTHER ZOONOSES IN TANZANIA

The epidemiology and control strategies of African trypanosomiasis, pl ague, rabies, brucellosis, anthrax and hydatidosis, the most important and well documented zoonotic diseases in Tanzania, have been describe d. Bovine tuberculosis, tetanus, taeniosis, trichinosis and tungosis a re also endemic in some parts of the country but records of their inci dences are not available. Initial outbreaks of trypanosomiasis in Tanz ania were caused by Trypanosoma gambiense which originated from West A frica and reached Tanzania via Zaire around 1902. T. rhodesiense which is currently responsible for human trypanosomiasis in Tanzania was in troduced from Mozambique around 1910 and quickly spread to many parts of the country. The disease is currently prevalent in the western, nor th and northwestern parts, the southern highlands and southern regions . Over 6000 cases have reported since 1979. Control strategies against sleeping sickness in Tanzania include chemical control of vectors, tr eatment of patients with trypanocides and avoidance of human-tsetse co ntact. Plague is mostly endemic in central, northern and north-eastern Tanzania. A total of 8161 cases with 1885 deaths have been recorded s ince 1890. The disease is currently prevalent in Lushoto district wher e outbreaks have been experienced since 1980, and in Singida district where it has been endemic since 1918. Integrated control measures are currently applied and were possibly responsible for the 1989 decline o f outbreaks in the area. Financial constraints which led to deteriorat ion of control activities from July 1989 probably accounted for the se vere outbreaks in 1990/91 which spread to other parts of the country. Rabies is endemic countrywide except in Mtwara, Lindi and Zanzibar. Do mestic dogs are the principal transmitters and prompt vaccination and destruction of unvaccinated stray dogs are the main control measures. Brucellosis is widely endemic in livestock and potentially so in human s. Destruction of infected animals, immunisation of susceptible ones, proper boiling of milk and its products and chemotherapy are the curre ntly applied control measures against the disease. Anthrax and hydatid osis are sparsely endemic in the country, and they are mostly controll ed by appropriate meat inspection and consequent condemnation and prop er disposal of the affected meat. Vaccination ind treatment of animals are also effective against anthrax.