Hepatitis B vaccine and liver problems in U.S. children less than 6 years old

Hepatitis B vaccination of male neonates and autism diagnosis, NHIS 1997-2002

Universal hepatitis B vaccination was recommended for U.S. newborns in 1991; however, safety findings are mixed. The association between hepatitis B vaccination of male neonates and parental report of autism diagnosis was determined. This cross-sectional study used weighted probability samples obtained from National Health Interview Survey 1997-2002 data sets. Vaccination status was determined from the vaccination record. Logistic regression was used to estimate the odds for autism diagnosis associated with neonatal hepatitis B vaccination among boys age 3-17 years, born before 1999, adjusted for race, maternal education, and two-parent household. Boys vaccinated as neonates had threefold greater odds for autism diagnosis compared to boys never vaccinated or vaccinated after the first month of life. Non-Hispanic white boys were 64% less likely to have autism diagnosis relative to nonwhite boys. Findings suggest that U.S. male neonates vaccinated with the hepatitis B vaccine prior to 1999 (from vaccination record) had a threefold higher risk for parental report of autism diagnosis compared to boys not vaccinated as neonates during that same time period. Nonwhite boys bore a greater risk.

In vivo transmission and dynamics of deleted genomes after experimental infection of woodchuck hepatitis B virus in adult animals

The presence of Deleted Genomes has been shown in a number of viral models including Hepadnaviridae. The analysis of woodchuck hepatitis B virus (WHV) population after experimental infection of woodchuck 197 (W197) with WHV7-PI inoculum revealed the presence of two Deleted Genomes: DG600 lacking a 1330 bp region (Core/Polymerase/PreS1) and DG900 showing a deletion of 869 nts (Pol/PreS/S). These mutants were also present in WHV7-PI. The successive WHV experimental infections in adult animals were performed using W197-w7 inoculum containing DG600 and DG900. Infections were divided into three groups presenting different patterns of viral replication, different presence of markers, occurrence of variants and persistence of infection. The first group displayed 2-3 weeks viremic phase and WHV-DNA titres of 10-30 ng/ml; the second a longer viremic phase (8-9 weeks) and higher WHV-DNA titres (up to 78 ng/ml). In contrast, the third group exhibited lifetime presence of WHV-DNA and WHVeAg in serum and viral replication in liver. The Deleted Genomes were transmitted in the newly infected animals with the same genomic organization. DG600 was persistently found only in chronically infected woodchuck, whereas a different pattern of presence was described for DG900. The characterization of these classes of deleted mutants in woodchuck-WHV model raises new questions on the link between DGs and persistent infections.