ABSTRACT
AIM: This is a cross-sectional study to determine the prevalence and risk factors for transmission of hepatitis B virus (HBV) infection in the Gezira state of central Sudan prior to the introduction of blood screening and vaccination against HBV. MATERIALS AND METHODS: The study was carried out on the population of Um Zukra village in Gezira state of Central Sudan. The village was surveyed on five consecutive days in Dec 2000. Epidemiological characteristics were recorded and participants were interviewed for risk factors of viral hepatitis. Blood samples were then collected and tested for HBsAg and HBcAb. RESULTS: A total of 404 subjects were screened with a mean age of 35 years; 54.9% were females, HBsAg and HBcAb were reactive in 6.9% and 47.5% of the studied population, respectively. Exposure to HBV increased with increasing age. The only significant risk factor for transmission of infection was a history of parenteral antischistosomal therapy. CONCLUSION: This study shows that prevalence of HBV infection is high in the studied population and it is hoped that introduction of blood screening and vaccination against HBV would decrease the carrier pool in the next few years.
ABSTRACT
Lethal disease in Schistosoma mansoni infections is mostly due to portal hypertension caused by hepatic periportal fibrosis. To evaluate the factors that may determine severe disease, livers and spleens were examined by ultrasound in a Sudanese population living in a village where S. mansoni is endemic. Early (FI), moderate (FII), or advanced (FIII) fibrosis was observed in 58%, 9%, and 3% of the population, respectively. Although FI affected 50%-70% of the children and adolescents, FII prevalence was low in subjects =20 years old but increased sharply (45%-58%) in men 21-30 years old and was associated with the highest infections. Portal and splenic vein diameters were increased in one-third of persons with FII and in almost all with FIII disease. Severe disease, FII or FIII with portal hypertension, affected 6% of the population, was associated with splenomegaly, occurred mostly in adult men, and was clustered in a few pedigrees. These observations suggest that infection intensity and duration, gender-related factors, and inherited factors are important in fibrosis development.