The Effect of Sewage Sludge Compost On the Viability of the Eggs of a Parasitic Nematode

Abstract

Ascariasis affects approximately one quarter of the world's population and is particularly prevalent in developing countries. As improvements in sanitation in most of these countries becomes more widespread, composting of human excreta and sewage sludge has become a popular and cost-effective method of treatment, as well as offering a valuable source of organic fertilizer and a soil amendment. If, however, the composting process is not properly controlled there may be a potential risk from pathogens, helminths and other infections to workers handling the compost and to consumers of foodstuffs grown on land treated with the compost.During this study the effect of sewage sludge compost on the viability of ascarid eggs was examined. Eggs of Ascaridia galli were used as a model for the eggs of the human pathogen Ascaris lumbricoides. Fully-developed A. galli eggs were added to sewage sludge compost suspensions, to microorganism-free compost filtrate suspensions and to distilled water controls. The results fro...