Sleeping sickness surveys: game reserve adjacent villages in Malawi
Although tsetse control measures were discontinued in Malawi in the early 1950s, the prevalence of sleeping sickness apparendy remained at low levels. A sleeping sickness survey conducted in 1987 to 1989 revealed a prevalence of the disease of 3% (103/3000). 7% (215/3000) of the individuals tested were positive for malaria. 87 in~ividuals traced 2 years after hospital discharge were found well and active in their villages. 4 died in villages after hospital treatment. 3 relapsed and were readmitted to hospital. Sera from 160 game ranger volunteers and from 82 suspected cases_of Rhodesian sleeping sickness were tested by use of ELISA, IF AT and CA TT. ELISA and CA TT, though not specific, proved to be useful tests for mass screening for human trypanosomiasis. Thick blood smear was found to be the best diagnostic method in this survey.