Control of morbidity due to Schistosoma haematobium on Pemba Island: egg excretion and hematuria as indicators of infection.
The variability of Schistosoma haematobium egg excretion using a quantitative syringe filtration technique and the variability of hematuria detected visually and by reagent strips were studied in a population of 520 subjects from the village of Pujini (Pemba Island, Zanzibar, Tanzania) for 6 consecutive days. A high degree of day-to-day variability of egg excretion within subjects was found both in the whole population and in the 5-19 year age group. Subjects with 1 urinary egg count of greater than or equal to 50 eggs/10 ml urine were not similarly classified in 36-61% of the other 5 examinations and 4-16% of their other examinations were negative. Gross hematuria had a specificity of almost 100%, when related to a positive filtration on any day, and was closely related to egg counts of greater than or equal to 50 eggs/10 ml urine. The finding of a strongly positive reaction for hematuria on a given single day was closely associated with the subject having a high egg count (greater than or equal to 50 eggs/10 ml urine) on at least one of the 6 days of the study. At the primary health care level, single highly positive semiquantitative values for hematuria were a more useful diagnostic indicator than a single egg count to select patients with heavy infections for selective population chemotherapy.
Savioli
L
L
Ministry for Foreign Affairs, Direzione Generale per la Cooperazione allo Sviluppo, Italy.
Hatz
C
C
Dixon
H
H
Kisumku
U M
UM
Mott
K E
KE
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006417:Hematuria / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D010270:Parasite Egg Count; D011237:Predictive Value of Tests; D015995:Prevalence; D012553:Schistosomiasis haematobia / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology; D013636:Tanzania / Q000453:epidemiology; D014556:Urine / Q000469:parasitology*