Molecular characterization of hepatitis B virus among chronic hepatitis B patients from Pointe Noire, Republic of Congo

Abstract

BackgroundChronic Hepatitis B infection is a major health problem in Republic of Congo therefore molecular analysis of HBV strains is important to detect the patients at high risk of disease progression.MethodsSerum samples were obtained from 111 chronic HBV patients in Pointe Noire. HBsAg, HBeAg and HBeAb were detected. A fragment of the preS1 region of HBV was amplified and sequenced to determine genotypes, subgenotypes and to identify mutations.ResultsOf the 111 samples analyzed, 35 patients were asymptomatic carriers (ASC), 24 with a chronic active hepatitis (CAH), 33 with liver cirrhosis (LC) and 19 have a hepatocellular carcinoma (HCC). The mean age were 45 ± 13 year, 88 (79.3 %) were male and 23 (20.7 %) female. The prevalence of HBeAg was 15.3 % and 73 % of subjects were anti-HBe positive. The mean serum level of alanine aminotransferase transaminase (ALT) and aspartate transaminase (AST) was 25.1 ± 9 IU/L and 28.6 ± 10 IU/L respectively. Eighty two samples out of 111 (73.9 %) were genotyped by the analyzing of the S region of HBV, 58 (70.7 %) cases belonged to HBV genotype E and 24 (29.3 %) were genotype A with three subgenotypes; A3 (66.7 %), A4 (20.8 %) and A6 (12.5 %). Prevalence of genotype A was relatively high in CAH (33.3 %) and HCC (31.6 %) patients in comparison with other groups. The most prevalent amino acids substitutions were R38K found in 14 (17.1 %) sequences, following by H44L in 11 (13.4 %), K13E in 8 (9.8 %), N29K in 8 (9.8 %), A35E in 8 (9.8 %), V80I in 7 (8.5 %) and in 6 (7.3 %) sequences for S90T. Different substitutions located in the hepatocyte binding site were higher among patients with LC and HCC (p < 0.05).ConclusionsThis study have shown that HBV genotype E and A were the most frequent strains circulating in Republic of Congo patients. HBV pres1 substitutions found in this study were associated with severe clinical forms of liver diseases. This data have shown the importance of implementing an effective program to fight HBV infection.

Seroepidemiology of Hepatitis B in the Democratic Republic of the Congo

“…8,12 Our findings also provide insight into the distribution of HBV genotypes in Central Africa. Similar to other analyses conducted in sub-Saharan Africa, [3][4][5][6]18 our phylogenetic analysis isolated genotypes A and E among HBsAg-positive samples. We also identified three unique genotype A sequences from the western provinces, although the lack of full-length genome sequences prevents us from determining whether they represent a novel subgenotype.…”

Molecular characteristics of chronic hepatitis B virus infection among voluntary blood donors in Kinshasa, Democratic Republic of the Congo

“…The new HBV/A strains we reported clustered into three subgenotypes, namely A1, A4 and quasi-subgenotype A3, the latter being the most frequent HBV/A subgenotype. This supports previous studies reporting HBV/A3 as predominant in West/Central Africa [26] The particularity of HBV/A4 is to be a recent HBV/A subgenotype that has so far been reported in very few Africa countries including DRC and two out of its neighbouring countries, namely Republic of Congo and Rwanda [16, 27]. This high HBV/A variability suggests that HBV has a long evolutionary history in Kinshasa, DRC.…”

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

“…Our sequences were closely related to A3 subgenotype strains found in Cameroon, Guinea and Nigeria. HBV subgenotype A4, reported regionally in Cameroon and the Republic of the Congo, was located in three southern provinces (Haut‐Ogooué, Ngounié and Nyanga) and in the more Northern province of Estuaire. Our identification of HBV‐E confirms previous studies showing that genotype E circulates in Gabon, improving evidence of its endemicity in Western and central Africa.…”

“…and the Republic of the Congo,45 was located in three southern provinces (Haut-HDV, hepatitis D virus antibody; OR, odds ratio. HDV exposure was measured as the presence or absence of anti-HDV among HBsAg+ individuals.…”