Prevalence and diversity of intestinal helminth eggs in pit latrine sludge of a tropical urban area

The aim of the study was to investigate the prevalence and diversity of helminth eggs in pit latrine sludge in Yaounde, Cameroon. A total of 30 faecal sludge samples were collected in various latrines and analysed for physico-chemical parameters and helminth eggs' characterization was undertaken using standard protocols. Effects of physico-chemical parameters (pH, temperature, salinity, electrical conductivity, chemical oxygen demand, biochemical oxygen demand for 5 days_, nitrogen ammonia, dry matter (DM), moisture content) on the parasite eggs were addressed. The total helminth egg concentration in the samples ranged from 8.5 eggs/g DM to a maximum of 264.5 eggs/g DM with a median of 81.1 eggs/g DM. Nematodes represented 67% of the total species followed by Trematodes and Cestodes. The helminth species with high prevalence in the sludge were Ascaris lumbricoides (41.4 eggs/g DM), Ankylostoma duodenale (31.5 eggs/g DM), Fasciola hepatica (34.9 eggs/g DM) and Trichuris trichiura (32.5 eggs/g DM). The physico-chemical parameters had no effect on the parasite concentration. Due to the high helminth egg concentrations in positive samples analysed, the need for proper health and environmental protection measures has to be stressed to prevent helminthic disease transmission due to untreated sludge discharge into the environment after pit latrine emptying or via direct agricultural use.