Schistosoma mansoni, intestinal parasites and perceived morbidity indicators in schoolchildren in a rural endemic area of western Côte d'Ivoire

Abstract

SummaryThere is a great need for rapid and low-cost identification of communities at high risk of intestinal schistosomiasis. We report the development of a questionnaire approach that may do so. In the first phase, 209 schoolchildren from 3 neighbouring villages in a rural area endemic for intestinal schistosomiasis in western Côte d'Ivoire were screened for Schistosoma mansoni and other helminths on 4 consecutive days using Kato-Katz thick smears. Daily infection prevalences of S. mansoni were high (60%᎐71%) and the cumulative infection prevalence was 92.3%. Infections with hookworms and Ascaris lumbricoides were also frequent, with cumulative prevalences of 60.8% and 38.3%, respectively. On day 3, the presence of Entamoeba histolytica/E. dispar and Giardia lamblia was assessed by a faecal concentration procedure. In the second phase, focus group discussions (FGD) were conducted: in each village one FGD with heavily infected children and one FGD with lightly or S. mansoni-uninfected schoolchildren to assess their perception of morbidity. The aim was to establish local terms indicating S. mansoni infections. 'Diarrhoea', 'blood in the stools', 'stomach disorders' and 4 terms in the local Yacouba/Dioula languages were frequently used by infected children. A simple questionnaire was then developed and the headteachers interviewed all schoolchildren individually. 'Blood in stools', gnon and toto were reported significantly more frequently among moderately and heavily S. mansoni-infected children than by those not or only lightly infected. The term gloujeu indicated borderline significance. The best diagnostic performance was found for 'blood in stool' (sensitivity: 47%; specificity: 76%; positive predictive value: 66%; negative predictive value: 60%). All schistosomiasis infections were treated with a single oral dose of praziquantel (40 mg/kg body weight) and the same questionnaire was re-administered 6 weeks post-treatment. Statistically significantly less children reported having had 'blood in stool' and 'gloujeu' after treatment (McNemar's ( 2 -test, P Ͻ 0.01). We conclude that 'blood in stool', 'gnon', 'toto' and 'gloujeu' are the most reliable reported symptoms for rapid and low-cost identification of communities that are at high risk of S. mansoni infections in Côte d'Ivoire.

Intestinal amoebiasis, giardiasis and geohelminthiases: their association with other intestinal parasites and reported intestinal symptoms

“…A potential confounding effect can be expected in areas with high levels of S. mansoni infections, since infected individuals report diarrhoea more often compared with non-infected individuals (GRYSEELS, 1992). In our own work in the same area we found an odds ratio of 1.7 (95% CI 04-3.6) for this association (UTZINGER et al, 1998). In summary, reported diarrhoea was the only useful symptom for the identification of E. histolytica/E. dispar infections in our population surveyed, while no useful sign or symptom was found for the other intestinal parasites.…”

“…The marked relationship between reported blood in stool and intestinal schistosomiasis caused by S. mansoni is described elsewhere (UTZINGER et al, 1998). In the present paper, emphasis is placed on E. histolytica/E.…”

“…This procedure was repeated over 5 consecutive days. Further details of the study area and the children surveyed are provided elsewhere (UTZINGER et al, 1998).…”

“…The day-to-day variation and the cumulative results of the different helminth infections derived from the 4 repeated Kato-Katz readings have been presented in detail elsewhere (UTZINGER et al, 1998). In brief, S. mansoni was the predominant helminth with a cumulative infection vrevalence of 92.3%.…”

Simple anamnestic questions and recalled water-contact patterns for self-diagnosis of Schistosoma mansoni infection among schoolchildren in western Côte d'Ivoire.

“…14,18 Other studies focused on individual diagnosis of S. mansoni, and self-reported blood in stool was found to give the best diagnostic performance, but sensitivity and specificity values were only moderate. [19][20][21][22] Another approach of risk assessment was used in Brazil, where sociodemographic variables and recalled water-contact patterns were investigated in addition to perceived symptoms as predictors for an infection with S. mansoni. Results showed that questionnaires might be an alternative for self-diagnosis of S. mansoni.…”