Seroprevalence and genotypic characterization of HBV among low risk voluntary blood donors in Nairobi, Kenya

Abstract

Background Hepatitis B virus (HBV) causes significant morbidity and mortality globally primarily due to its ability to cause hepatitis, liver cirrhosis and hepatocellular carcinoma. The Kenya National Blood Transfusion Services screens for Hepatitis B antibodies using the chemiluminescent microparticle immunoassay method. This test does not inform on the genotypic characteristics of the virus or the actual presence of the virus in blood. This study therefore sought to determine the serologic and genotypic profiles of HBV circulating among the voluntary blood donors in Nairobi. Methods Blood samples were collected in plain and EDTA vacutainers and tested for the Hepatitis B surface antigen (HBsAg). HBV DNA was then extracted from plasma, its overlapping P/S gene amplified and sequenced. The resulting sequences were used to analyze for the circulating genotypes and mutations within the P and S genes. Bivariate statistical analysis was used to determine the association between demographic factors and HBV infection. Results A seroprevalence of 2.3% (n = 7) was reported. The age group 19–28 years was significantly associated with HBV infection. Nine samples were positive for HBV DNA; these included 2 HBsAg positive samples and 7 HBsAg negative samples. Genotype A, sub genotype A1 was found to be exclusively prevalent while a number of mutations were reported in the “a” determinant segment of the major hydrophilic region of the S gene associated with antibody escape. RT mutations including mutation rt181T in the P gene conferring resistance against Lamivudine and other ʟ-nucleoside drugs were detected. Conclusion There is a high prevalence of occult HBV infections among these blood donors and therefore the testing platform currently in use requires revision.

Estimating the Transmission Risks of Viral Hepatitis and HIV Among Blood Donors in Hossana, Southern Ethiopia

“…[40][41][42][43][44] This study revealed the overall magnitude of three common viral TTIs in the donor population was 14.4%. This finding is somewhat similar to that of studies conducted in Easter region, Jigjiga 11.5% 50 and Northwest region, Felege Hiwot 13.3% 17 in Ethiopia and other developing countries; 12.0% in Kenya, 7 13.7% in Eritrea, 20 13.0% in Nigeria 5 but lower studies reported in other locations of south Ethiopia; 29.5% in Sodo Wolaita, 11 and 43.2% in Bahir Dar 8 and other African countries; 29.85% in Burkina Faso, 30 21.2% in Cameroon 32 and 37.4% in Equatorial Guinea. 49 This is probably because of the actual differences in study, population, duration, variation in occupation, and geographical differences of the study populations; moreover, the prescreening procedure may also play a role in the observed variations.…”

“…4,5 About 350 million people worldwide are chronically infected with HBV, more than 71 million with HCV, and 38 million with HIV. 6,7 The prevalence of TTIs among blood donors is widely used as an indicator of the problem. [8][9][10] In several settings, HBV, HCV, and HIV are the major TTIs.…”

Disproportionate Distribution of HBV Genotypes A and D and the Recombinant Genotype D/E in the High and Low HBV Endemic Regions of Uganda: A Wake-Up Call for Regional Specific HBV Management

“…This research was aimed at establishing the circulating hepatitis B virus genotypes in a low and a high endemic region of Uganda in order to give a plausible explanation for the regional differences in disease burden. The nucleotide sequence analysis of the hepatitis B virus DNA polymerase gene in all patient samples from the low and high endemic regions detected genotypes A and D consistent with earlier studies in other African countries including Tunisia [ 27 ], Gambia, Nigeria, Congo, Rwanda, Cameroon [ 34 ], Egypt [ 35 ], Central African Republic [ 36 ], South Africa [ 20 ], Morocco [ 37 ], Kenya [ 38 ], and Uganda [ 9 ]. Besides, a high proportion of the D/E recombinant genotype mildly reported in Uganda by Zirabamuzaale and Ocama [ 9 ] has been prominently reported in our study.…”

Comparative Seroprevalence of Hepatitis B Virus among in-Mates and Low Risk Voluntary Blood Donors in Garissa, Kenya

“…The HBV seroprevalence in voluntary blood donors was marginally higher compared to the 2.3% seroprevalence recorded in the same group in a study carried out in Nairobi, Kenya using the chemiluminescent microparticle immunoassay (CMIA) [8] and similar to (3.46%) seroprevalence from a study carried out in Kisumu, Homabay and Siaya Counties, Kenya using ELISA and confirmed by CMIA [7].…”

“…Kenya has been categorized with other sub-Saharan African countries with a HBV infection burden of chronic states of intermediate range (2% -7%) and high (≥8%) [4]. Studies have shown HBV infection disparity in Kenya among various study populations, with 5.1% prevalence in areas near Nairobi among rural settler community, 15.3% in Turkana County among pregnant women [6], 3.46% in Kisumu, Homabay and Siaya Counties [7] and 2.3% in Nairobi [8] among blood donors. Diagnosis of HBV is routinely done by measurement of various HBV specific antigens and antibodies.…”