Recent Population Expansions of Hepatitis B Virus in the United States

Abstract

The recent epidemic history of hepatitis B virus (HBV) infections in the United States is complex, as indicated by current disparity in HBV genotype distribution between acute and chronic hepatitis B cases and the rapid decline in hepatitis B incidence since the 1990s. We report temporal changes in the genetic composition of the HBV population using whole-genome sequences (n ‫؍‬

Geographic distribution and characteristics of genotype A hepatitis B virus infection in acute and chronic hepatitis B patients in Japan

“…Based on sequencing data from the USA, subtype A2(e) strains of AHB from men who have sex with men (MSM) tend to cluster phylogenetically, which indicates selective expansion of specific strains, and are significantly limited in genetic diversity. 24 Other reports from western countries have also shown sharp increases in acute infections with subtype A2(e) strains linked to high-risk practices, such as MSM activity and injection drug use. 25,26 These strains are thought to have been transmitted by foreign-born MSM and spread among subsets of the Japanese population who share specific sexual behaviors.…”

“…All of the 65 strains isolated from the AHB patients with genotype A in this study were classified into subtype A2 (Ae). Based on sequencing data from the USA, subtype A2(e) strains of AHB from men who have sex with men (MSM) tend to cluster phylogenetically, which indicates selective expansion of specific strains, and are significantly limited in genetic diversity . Other reports from western countries have also shown sharp increases in acute infections with subtype A2(e) strains linked to high‐risk practices, such as MSM activity and injection drug use .…”

Recent and occult hepatitis B virus infections among blood donors in the United States

“…Genotype A accounted for 35% of the US cases of chronic hepatitis B in 2001 . A rapid population expansion in A2 strains appeared to occur between 1995 and 2002 in the United States, with A2 representing the overwhelming majority of genotype A strains circulating in the United States now …”

“…DNA sequencing involved a 435‐base‐pair DNA segment amplified from the HBV S gene (between nucleotide positions 222 and 656), as previously described …”

Adoptive donor immunity protects against resolved hepatitis B virus reactivation after allogeneic haematopoietic stem cell transplantation in the world's largest retrospective cohort study

“…More than 2 billion people have been exposed to hepatitis B virus (HBV) worldwide (Schweitzer et al, 2015). Even in the non-endemic United States (Ioannou, 2011;Ramachandran et al, 2014;Martin et al, 2015) and Europe (Hope et al, 2014), approximately 1 and 13 million individuals, respectively, have chronic HBV infection, and 43 000 new infections occur annually in the United States (Ramachandran et al, 2014). Following recovery from chronic HBV infection, patients may evolve into a state of resolved HBV infection (rHBV), defined as negative HBV surface antigen (HBsAgÀ) and positive HBV core antibody (anti-HBc+).…”