THE EPIDEMIOLOGY OF SCHISTOSOMA-MANSONI, HEPATITIS-B AND HEPATITIS-C INFECTION IN EGYPT

There appears to be no epidemiological association between Schistosoma mansoni infection, the intensity of S. mansoni infection or S. mansoni infection complicated by schistosome hepatic fibrosis and the presence of antibody to hepatitis B virus core antigen (anti-HBc), hepatitis B surface antigen (HBsAg), antibody to hepatitis C virus (anti-HCV) or antibody to both agents. This was the main conclusion of a population-based study of an entire village in the northern Egyptian Nile Delta. All 1850 villagers were invited to participate and serological, parasitological and ultrasound examinations were completed on a high proportion of the total population (68% provided sera and higher percentages provided stool specimens and were subjected to ultrasound examinations). Testing with dual Kato slides indicated a high prevalence of S. mansoni infection in the village (49.1%), typical of the area. Hepatitis B virus (HBV) markers (presence of either anti-HBc and/or HBsAg) and anti-HCV were also found to be prevalent, present in 24% and 15.9% of the villagers, respectively. The age-adjusted odds ratios (OR) for infection with S. mansoni and HBV [1.13; 95% confidence interval (CI)=0.87-1.48], HBsAg (1.11; CI=0.47-2.58), or anti-HCV (1.02; CI=0.7-1.37) were not significantly greater than unity. Similarly low and non-significant OR estimates were observed with those positive for both HBV and anti-HCV. No other outcome measures of S. mansoni infection (i.e. intensity of infection or ultrasonographically-determined schistosomal hepatic fibrosis) were found to be associated with HBV, HBsAg or anti-HCV. This study confirms the lack of association of S. mansoni and HBV markers seen in previous studies and further extends this lack of association to anti-HCV.