Scabies and Pyoderma in Lilongwe, Malawi. Prevalence and seasonal fluctuation.

From January 1988 to June 1989, data were collected daily on the patients who were seen at the Dermatology Clinic attached to the Kamuzu Central Hospital, Lilongwe, Malawi. Cases were diagnosed and patients were treated under the supervision of a dermatologist. A total of 34,002 patients were seen during the study period. Of these patients, 15,526 (45.7%) were children and 18,476 (54.3%) were adults. The prevalence of scabies was 40.4% in children and 31.6% in adults, whereas the prevalence of impetigo/bacterial skin infections was 26% in children and 10.4% in adults. Based on data accumulated for periods of 1 month, the incidence rate of scabies was highest during the cold, dry season (May-November) and the incidence rate of skin infection was highest during the hot, rainy season (December-April). Since the patients who were studied lived predominantly in rural settings, an explanation for the higher incidence rate of scabies during the cold season could be close body contact resulting from the overcrowding within the houses. The reason for the increase in the incidence rate of pyoderma during the rainy season might be linked to deficiencies in hygienic precautions. A community-based intervention strategy with children as its target population is proposed to combat these diseases.