Broad Range of Hepatitis B Virus (HBV) Patterns, Dual Circulation of Quasi-Subgenotype A3 and HBV/E and Heterogeneous HBV Mutations in HIV-Positive Patients in Gabon

Abstract

Integrated data on hepatitis B virus (HBV) patterns, HBV genotypes and mutations are lacking in human immunodeficiency virus type 1 (HIV-1) co-infected patients from Africa. This survey was conducted in 2010–2013 among 762 HIV-1-positive adults from Gabon who were predominantly treated with 3TC-based antiretroviral treatment. HBV patterns were identified using immunoassays detecting total antibody to hepatitis B core antigen (HBcAb), hepatitis B surface antigen (HBsAg), IgM HBcAb, hepatitis B e antigen (HBeAg), antibody to HBsAg (HBsAb) and an in-house real-time PCR test for HBV DNA quantification. Occult hepatitis B (OBI) was defined by the presence of isolated anti-HBc with detectable serum HBV DNA. HBV genotypes and HBV mutations were analyzed by PCR-direct sequencing method. Seventy-one (9.3%) patients tested positive for HBsAg, including one with acute hepatitis B (0.1%; 95% CI, 0.0%-0.2%), nine with HBeAg-positive chronic hepatitis B (CHB) (1.2%; 95% CI, 0.6%–2.2%), 16 with HBeAg-negative CHB (2.1%; 95% CI, 1.2%–3.3%) and 45 inactive HBV carriers (5.9%; 95% CI, 4.4%–7.8%). Sixty-one (8.0%; 95% CI, 6.2%–10.1%) patients showed OBI. Treated patients showed similar HBV DNA levels to those obtained in untreated patients, regardless of HBV patterns. Around 15.0% of OBI patients showed high (>1,000 UI/mL) viremia. The mutation M204V/I conferring resistance to 3TC was more common in HBV/A (47.4%) than in HBV/E isolates (0%) (P = .04). Our findings encouraged clinicians to promote HBV vaccination in patients with no exposure to HBV and to switch 3TC to universal TDF in those with CHB.

HBV Genotypes and Drug Resistance Mutations in Antiretroviral Treatment-Naive and Treatment-Experienced HBV–HIV-Coinfected Patients

“…Other studies have reported primary 3TC resistance due to rt181T/S substitutions [10]. HBV mutations also occur in the absence of 3TC therapy and are thought to occur naturally in HBV carriers who have not been treated with the drug, implying that pre-existing mutations may be transmitted or contribute toward early emergence of 3TC resistance during therapy [11, 12]. …”

Pfmdr1 gene polymorphism of Plasmodium falciparum isolates from asymptomatic individuals of Dienga, southeastern Gabon

“…The increase of genotype N86 has been associated with a decreased susceptibility to artemisinins in vitro [36,37].…”

High prevalence and diversity of hepatitis B and hepatitis delta virus in Gabon

“…Previous sero‐epidemiological studies conducted between 1988 and 2009 in Gabon showed a high prevalence of HBsAg (>8%) in various populations within the provinces of Haut‐Ogooué, Ngounié, Woleu‐Ntem and Ogooué‐Ivindo and that about 60.0% of HBsAg positive individuals in Woleu‐Ntem had antibodies to HDV . In these few, often restricted, study populations, circulation of HBV genotypes A3, A4, and E and HDV genotypes 1, 7, and 8 were reported …”

“…[23][24][25][26] In these few, often restricted, study populations, circulation of HBV genotypes A3, A4, and E and HDV genotypes 1, 7, and 8 were reported. [24][25][26][27][28] Screening for HBV is carried out mainly in blood transfusion centres, after blood exposure accidents or in symptomatic patients (clinical jaundice) but broad therapeutic coverage does not extend to patients living in rural areas, despite a national policy of Universal Health Coverage and the existence of a social health insurance. Furthermore, HBV vaccination has been implemented in infants in urban areas in Gabon since 2005, with an estimated immunization coverage between 71% to 82%, and to date, there is no HBV vaccination program in rural areas.…”