Horizontal transmission of hepatitis B virus among children and adults in five rural villages in Zambia

Abstract

To determine whether horizontal transmission of the hepatitis B virus contributes to the high prevalence of infection with this virus in an endemic region, residents of five villages in Zambia were tested for hepatitis B serologic markers. The prevalence of hepatitis B was determined by testing samples from 620 residents. By examining paired serum samples from 79 children and 80 adults, it was determined that new infections occurred during the five years of this study in at least 14 children (18%) (aged 4-17 years) and ten adults (12%) (aged 23-65 years). These 24 new infections were distributed among 20 households and were not associated with active HBV infections in the mother or, in most cases, other family members. Intervention to prevent hepatitis B in regions such as rural Zambia will require vaccination of susceptible children and adults as well as newborn infants.

Epidemiological patterns of hepatitis B virus (HBV) in highly endemic areasr

“…Developed includes 1 survey from UK [81] and Italy [82]. [43] for details (solid line, Zambia [27]; dotted line, Nairobi [28]; dashed line, The Gambia [26]; +, Khalawaat, Sudan [29]; A, Saleim, Sudan [29]; x , Senegal [30]; and O, South Africa [31]). (b) Maximum-likelihood estimates from 6 surveys in east Asia (solid line, Taiwan [32]; dotted line, Kinalaglagan, Philippines [33]; dashed line, Tagumpay, Philippines [33]; +, Santa Rosa, Philippines [33]; A, Agoho, Philippines [33]; and x, Shanghai [34]).…”

“…Anti-HBc is passed across the placenta and is present in breast-milk, but it is not a protective antibody. The [26], Zambia [27], Nairobi [28], Senegal [30], South Africa [31], Taiwan [32], four surveys from the Philippines [33] and one from Shanghai [34]. In addition to the surveys from sub-Saharan Africa and east Asia, three more studies from other highly endemic populations were included, from French Polynesia [35], Solomon Islands [36] and Venezuela [37].…”

Seroepidemiology of hepatitis B virus in Addis Ababa, Ethiopia: transmission patterns and vaccine control

“…Cross-sectional community studies of serological markers of HBV infection have an important role in identifying population endemicity, possible routes of transmission and associated risk factors [1][2][3][4][5][6][7][8][9]. Such data help in the development of appropriate control measures, for example, estimating the optimal age for vaccine delivery, the level of vaccine coverage required for elimination, and possible high-risk target groups [10,11].…”

Recombination in the Genesis and Evolution of Hepatitis B Virus Genotypes

“…It is responsible for substantial proportion of liver disease that kills over one million people through uncompensated liver disease or hepatocellular carcinoma each year (43). Populations in South and East Asia, sub-Saharan Africa, and Central and South America show particularly high frequencies of HBV infection that may be maintained through mother-tochild perinatal transmission (13) or horizontal transmission in childhood (8,41).HBV variants infecting humans show genetic and antigenic heterogeneity and are currently classified into seven or eight genotypes that differ from each other in nucleotide sequence by 10 to 13% (29-31, 33). While genotypes A, D, and possibly G have global distributions, genotypes B and C are found predominantly in East and Southeast Asia, genotype E is found in West Africa, and genotypes F and H are found among various population groups, including indigenous peoples in Central and South America.…”