Molecular epidemiology of hepatitis B virus in Dakar, Sénégal

Abstract

Using DNA chip technology and real-time quantitative PCR, molecular profile of HBV strains infecting blood donors and patients in Dakar, Sénégal was studied. All HBsAg-positive blood donors (n = 175) and all patients who presented with chronic hepatitis B (n = 29) between 1st June 2003 and 31st July 2003 were studied. One patient, a blood donor, was coinfected by HCV, and nine patients had anti-HDV antibodies. Few persons in either group were HBeAg-positive. Viral load values were relatively low but correlated with biochemical abnormalities. Patients were infected mainly by genotype E (72%). Patients infected by genotype A (28%) tended to be younger than other patients. There was no significant difference between the blood donors and the patients with hepatitis B as regards virological markers, including viral load, when the HBV genotype was taken into account. The BCP A1762T and G1764A mutations were found in four patients and one patient, respectively; the two mutations were never found in the same patient. The W28* mutation at position 1896 of the core was detected in 19 of the 32 genotyped patients, 18 (83%) of whom had genotype E infection. ALT levels were not influenced by HBV mutations. This study shows a low frequency of clinical signs in HBsAg-positive blood donors, a relatively low level of viral replication, and a high frequency of pre-core mutants in this West African population. These results underline the importance of molecular characterization of HBV infection as specific treatments become available in this region.

Molecular epidemiology and genetic diversity of hepatitis B virus genotype E in an isolated Afro-Colombian community

“…Also, this genotype has been reported from other West African countries like Senegal (Vray et al, 2006), the Ivory Coast (Suzuki et al, 2003), Ghana (Candotti et al, 2006), Gambia (Dumpis et al, 2001), Angola and Namibia (Kramvis & Kew, 2007). Finally, some strains were reported further East in Madagascar and Mozambique (Cunha et al, 2007;Kramvis et al, 2005).…”

Hepatitis B virus genotype E variability in Africa

“…3,12,13 As a result of the co-circulation of these two genotypes, recombinations and a high number of mixed infections were detected. 12 Genotype E was also reported from other West African countries like Senegal, 19 Ivory Coast, 20 Ghana, 21 The Gambia, 22 Angola and Namibia. 2 In addition, a few strains were found further east like in Mozambique 23 and Madagascar 24 and Tunisia 25 in the North.…”

Microarray for Hepatitis B Virus Genotyping and Detection of 994 Mutations along the Genome

“…However, this is also the case for sequencing, for which performance also varies according to the codons. Repeated sequences (35) and insertions and deletions longer than 5 bp (36) were not encountered in the panel used for our study.…”

“…This technology has been used to analyze the genome of the virus in cohorts of patients with dual HIV-HBV infections (14) and in patients from sub-Saharan Africa (35). The present version of the assay implements several improvements, and although problems linked to the low GC content observed at some positions reduce the performance for the diagnosis of resistance to adefovir, as well as mutations in the BCP, its main advantage compared to Sanger sequencing is that it can provide exhaustive information at multiple positions along the whole 3.2-kb genome in a single reaction.…”