Are measurements of intensity of infection or morbidity necessary to evaluate schistosomiasis control within PHC?

Techniques that can be used to monitor changes in morbidity in large scale control schemes carried out through the PHC structure by a local health administration differ from those that can be used in well funded, small scale research programmes. Above all they must be cheap, simple, rapid and objective. They should demonstrate the effects of intervention soon after it has taken place and be directed to phenomena that have high prevalences. Monitoring of liver and spleen size in S. mansoni foci to some extent meets these criteria but can only be seen as an adjunct to quantitative microscopy. Urinalysis with reagent strips, or even simpler methods, may have a more important role in evaluating control of urinary schistosomiasis and practical constraints may make it easier to carry out than quantitative microscopy. However, the latter conveys more information and is of greater value in planning and urinalysis must be seen as an inadequate substitute for quantitative microscopy.