Viral Hepatitis B Genotypes among Outpatient Clinic Attendees in North Rift, Kenya

Abstract

Objective Most hospital outpatients unaware of their Hepatitis B Virus (HBV) status could be seeking treatment for other different ailments in Kenya. To evaluate the HBV prevalence and the genetic diversity, the genetic analysis of the partial HBV S gene was conducted. Methods Two hundred blood samples were collected from consenting outpatients who were unaware of their HBV status at Moi Teaching and Referral Hospital (MTRH), Kenya, between September 2015 and October 2016. The serum was tested for the HBV surface antigen (HBsAg) using the ELISA test. DNA was extracted from HBsAg positive samples, amplified and sequenced for HBV S gene. The sequences were then compared with reference sequences retrieved from the GenBank. Results Ten percent of subjects (20/200) were positive for HBsAg. Thirteen of the 14 isolates (92.9%) belonged to HBV sub genotype A1 (HBV/A1). In all the 14 isolates either one or more mutation was detected within Major Hydrophilic Region (MHR). The most occurring mutation was S114T which appeared in 13 of 14 isolates. No known mutations associated with occult HBV infection or vaccine escape were observed. Conclusion Ten percent of outpatients at MTRH could be a source of unaware HBV transmission in the community. HBV/A1 remains the most predominant genotype. The findings that the HBsAg mutations in MHR were observed in all isolates revealed the importance of monitoring the MHR mutations in this country. The development of an optimized HBV screening, vaccine program and a monitoring system of MHR mutation are urgently needed in North Rift Kenya.