Transmission of Hepatitis B and Hepatitis Delta Viruses in the Households of Chronic Hepatitis B Surface Antigen Carriers: A Regression Analysis of Indicators of Risk

Abstract

To evaluate whether clinical and laboratory features of a hepatitis B surface antigen (HBsAg) carrier can predict risks of infection, its chronicity, and the development of liver disease among close contacts, the authors studied a cohort of 994 first degree relatives or cohabitants (household contacts) of 226 non-drug-addicted chronic HBsAg carriers (index cases), of whom 77% had liver disease and 26% were superinfected by hepatitis D virus (HDV). A logistic form of regression analysis was used to assess the role of each feature in the index case as predictor of hepatitis B virus (HBV)- and HDV-related outcomes among household contacts. Six models of risk, expressed as odds ratios, were assessed by multivariate step-down analysis, with the following results. 1) Infection with HBV in the household contact was independently predicted by the index case being son, sibling, spouse, female, or HBV-DNA positive. 2) Chronic HBsAg carriage in the adult household contact was associated with female sex of the index case and with being a sibling; among young subjects, household contacts were more likely to be chronic HBsAg carriers when the index case was the mother, a sibling, or an HBV-DNA-positive subject. 3) HBV-DNA positivity in the young contact was more likely when the index case was HBV-DNA positive and when she was the mother. 4) HBV-DNA positivity in the absence of hepatitis B e antigen (HBeAg) in serum in the index case was not related to a similar pattern of infection in HBsAg-positive contacts. 5) Super-infection with HDV of an HBsAg-positive household contact was significantly predicted by female sex of the index case and by anti-HDV positivity. 6) Chronic liver disease in a contact was predicted only by HDV superinfection of the index case. We conclude that horizontal, nonparenteral transmission of HBV among siblings plays a major role in the household of HBsAg carriers from an intermediate endemicity area.

The long-term course of chronic hepatitis B

“…All patients came from Southern Italy, a geographical area where HBV infection, up to 10 years ago, took place mostly during the first years of life, and where coinfection with HDV is not uncommon. 19 Our cohort is thus representative of a specific sociodemographic reality, and results may not be generalizable to populations with different modes of HBV transmission and different immunogenetics, such as Asia, Central Europe, or North America.…”

Phylogenetic analysis of isolates from new cases of HBV infection in Southern Italy

“…The high incidence of HBV/D genotype in Sicilian patients with chronic infection, infected more than 15 years, it was associated with the circulation of endemic strains transmitted mostly by intrafamilial spread, as previously demonstrated (Craxì et al, 1991). Instead, phylogenetic analysis of viral isolates from new cases of HBV infection showed the presence of A genotypes not endemic in Sicily introduced mainly through sexual promiscuity and unsafe.…”

Background paper to the revised recommendation for hepatitis B vaccination of persons at particular risk and for hepatitis B postexposure prophylaxis in Germany

“…Living together with an HBsAg carrier was reported in 35 cases (5% of all notifications) as possible cause of infection Craxi et al [12] Cohort study, Italy Transmission in households with HBsAg carriers plays a major role in spread of hepatitis B, particularly among siblings Franks et al [13] Cohort study, US HBsAg carriers can transmit hepatitis B within households, but also between households Persons with high-risk sexual behavior van Houdt et al [14] Cohort study (n=1862), the Netherlands…”

“…F Indication group 2: Persons at increased risk of non-occupational exposure.Examples: Persons living together with HBsAg carriers [11,12,13], persons at high risk of acquiring hepatitis B by sexual contact [11,14,15], people who inject drugs [14,16,17], prison inmates [18,19,20], psychiatric inpatients [21,22]. F Indication group 3: Persons at increased risk of occupational exposure.Examples: Health care personnel (HCP) at risk of exposure (including trainees, laboratory personnel, cleaning personnel) [23,24,25], first aiders [26,27], police officers [29], personnel of facilities where an increased prevalence of HBV-infected persons is likely to be present (e.g., correctional facilities, asylum seeker shelters, homes for the handicapped) [18,19,20,27,28,29].…”