Temitope Oluwasegun Cephas Faleye1, Olubusuyi Moses Adewumi2, Ijeoma Maryjoy Ifeorah3, Adegboyega Akere4, Adeleye Solomon Bakarey5, Ewean Chukwuma Omoruyi6, Kemi Oketunde7, Oluwajumoke Bosede Awonusi8, Modupe Racheal Ajayi9, Johnson Adekunle Adeniji10. 1. Department of Virology, College of Medicine, University of Ibadan, Ibadan, Oyo State, Nigeria; Department of Microbiology, Faculty of Science, Ekiti State University, Ado Ekiti, Ekiti State, Nigeria. Electronic address: faleyetemitope@gmail.com. 2. Department of Virology, College of Medicine, University of Ibadan, Ibadan, Oyo State, Nigeria. Electronic address: adewumi1@hotmail.com. 3. Department of Surgery, College of Medicine, University of Ibadan, Ibadan, Oyo State, Nigeria. Electronic address: maryjoy1023@yahoo.ca. 4. Department of Medicine, College of Medicine, University of Ibadan, Ibadan, Oyo State, Nigeria. Electronic address: adeakere@yahoo.co.uk. 5. Institute for Advanced Medical Research and Training, College of Medicine, University of Ibadan, Ibadan, Oyo State, Nigeria. Electronic address: drbakarey@yahoo.com. 6. Institute of Child Health, College of Medicine, University of Ibadan, Ibadan, Oyo State, Nigeria. Electronic address: omochukwu2001@yahoo.com. 7. Department of Science Laboratory Technology, Faculty of Science, Ekiti State University, Ado Ekiti, Ekiti, State, Nigeria. Electronic address: oluwakemisolavera@gmail.com. 8. Department of Science Laboratory Technology, Faculty of Science, Ekiti State University, Ado Ekiti, Ekiti, State, Nigeria. Electronic address: b_jummy@yahoo.com. 9. Department of Microbiology, Faculty of Science, Ekiti State University, Ado Ekiti, Ekiti State, Nigeria. Electronic address: ajayimodupe@yahoo.com. 10. Department of Virology, College of Medicine, University of Ibadan, Ibadan, Oyo State, Nigeria; WHO National Polio Laboratories, University of Ibadan, Ibadan, Oyo State, Nigeria. Electronic address: adek1808@yahoo.com.
Abstract
BACKGROUND: In 2012, the first Nigerian Hepatitis B Virus (HBV) immune escape mutant (IEM) case was detected in a pregnant woman in southwestern Nigeria. Consequently, this study was designed to investigate the presence and possible circulation of IEMs amongst asymptomatic community dwellers in southwestern Nigeria. METHODS: Blood specimens collected from 438 asymptomatic community dwellers were screened for HBsAg using ELISA technique. Subsequently, the S-gene was amplified in HBsAg positive samples by a nested PCR protocol, and amplicons sequenced. Isolates were then subtyped by amino acid residues at positions 122, 127, 134 and 160, and genotyped by phylogenetic analysis. RESULTS: Of the 31 (7.08%) samples positive for HBsAg, the ∼ 408 bp Sgene fragment was successfully amplified and sequenced in 27. Samples obtained from 4 patients could not be amplified due to low titres. Sequence data from only 15 of the isolates could be analysed further as eight of the remaining 12 had multiple peaks while the rest three showed no similarity to any HBV gene when subjected to BLAST analysis. Thirteen of the 15 isolates were identified as genotype E. Eleven of which were subtyped as ayw4 while the remaining two could not be subtyped due to sR122Q/P substitutions. The last two isolates that could not be genotyped and subtyped had other mutations in the "a" determinant associated with IEMs. CONCLUSIONS: This study confirmed presence and circulation of HBV IEM in Nigeria, the country's inclusion in the genotype E crescent, and the value of phylogenetic analysis in HBV identification.
BACKGROUND: In 2012, the first Nigerian Hepatitis B Virus (HBV) immune escape mutant (IEM) case was detected in a pregnant woman in southwestern Nigeria. Consequently, this study was designed to investigate the presence and possible circulation of IEMs amongst asymptomatic community dwellers in southwestern Nigeria. METHODS: Blood specimens collected from 438 asymptomatic community dwellers were screened for HBsAg using ELISA technique. Subsequently, the S-gene was amplified in HBsAg positive samples by a nested PCR protocol, and amplicons sequenced. Isolates were then subtyped by amino acid residues at positions 122, 127, 134 and 160, and genotyped by phylogenetic analysis. RESULTS: Of the 31 (7.08%) samples positive for HBsAg, the ∼ 408 bp Sgene fragment was successfully amplified and sequenced in 27. Samples obtained from 4 patients could not be amplified due to low titres. Sequence data from only 15 of the isolates could be analysed further as eight of the remaining 12 had multiple peaks while the rest three showed no similarity to any HBV gene when subjected to BLAST analysis. Thirteen of the 15 isolates were identified as genotype E. Eleven of which were subtyped as ayw4 while the remaining two could not be subtyped due to sR122Q/P substitutions. The last two isolates that could not be genotyped and subtyped had other mutations in the "a" determinant associated with IEMs. CONCLUSIONS: This study confirmed presence and circulation of HBV IEM in Nigeria, the country's inclusion in the genotype E crescent, and the value of phylogenetic analysis in HBV identification.
Authors: Jennifer Grant; Oche Agbaji; Anna Kramvis; Mukhlid Yousif; Mu'azu Auwal; Sudhir Penugonda; Placid Ugoagwu; Robert Murphy; Claudia Hawkins Journal: Trop Med Int Health Date: 2017-05-22 Impact factor: 2.622
Authors: Chinenye F Umego; Clement I Mboto; Atim D Asitok; Linda C Osaji; Uwem E George; Uwem O Edet; Elizabeth N Mbim; Temitope Oc Faleye; Olubusuyi M Adewumi; Johnson A Adeniji Journal: Afr Health Sci Date: 2022-03 Impact factor: 1.108