title: Hepatitis B infection is highly prevalent among patients presenting with jaundice in Kenya.
abstract: BACKGROUND
  Viral hepatitis is a major concern worldwide, with hepatitis A (HAV) and E (HEV) viruses showing sporadic outbreaks while hepatitis B (HBV) and C (HCV) viruses are associated with chronic hepatitis, cirrhosis and hepatocellular carcinoma. The present study determined the proportion, geographic distribution and molecular characterization of hepatitis viruses among patients seeking medical services at hospitals throughout Kenya.
  
  
  METHODS
  Patients presenting with jaundice at four selected hospitals were recruited (n = 389). Sera were tested for the presence of antibody to hepatitis viruses A through E, and HBV surface antigen (HBsAg). Nucleic acid from anti-HAV IgM antibody and HBsAg positive samples was extracted, amplified and sequenced.
  
  
  RESULTS
  Chronic HBV infection was the leading cause of morbidity among patients with symptoms of liver disease seeking medical help. Incident HCV, HEV and HDV infection were not detected among the patients in this study, while the proportion of acute HAV was low; HAV IgM positivity was observed in 6.3 % of patients and sequencing revealed that all cases belonged to genotype 1B. HCV seropositivity upon initial screening was 3.9 % but none were confirmed positive by a supplementary immunoblot assay. There was no serological evidence of HDV and acute HEV infection (anti-HEV IgM). HBsAg was found in 50.6 % of the patients and 2.3 % were positive for IgM antibody to the core protein, indicating probable acute infection. HBV genotype A was predominant (90.3 %) followed by D (9.7 %) among HBV DNA positive specimens. Full genome analysis showed HBV/D isolates having similarity to both D4 and D6 subgenotypes and D/E recombinant reference sequences. Two recombinant sequences demonstrated > 4 % nucleotide divergence from other previously known D/E recombinants.
  
  
  CONCLUSIONS
  HBV is highly prevalent among patients seeking care for symptoms consistent with hepatitis, compared to the general population. Molecular characterization of HBV isolates indicated recombinant strains that may give rise to new circulating variants. There is a need to document the prevalence, clinical manifestation and distribution of the variants observed. HAV genotype 1B, prevalent in Africa, was observed; however, the absence of HCV, HDV and acute HEV in this study does not rule out their presence in Kenya.
authors.affiliation: Kenya Medical Research Institute (KEMRI), Nairobi, Kenya. omissiani@gmail.com.
authors.forename: Missiani
authors.initials: M
authors.lastname: Ochwoto
authors.affiliation: Kenya Medical Research Institute (KEMRI), Nairobi, Kenya. JHkimotho@kemri.org.
authors.forename: James H
authors.initials: JH
authors.lastname: Kimotho
authors.affiliation: Medical Microbiology Department, University of Nairobi, Nairobi, Kenya. julias.oyugi9@gmail.com.
authors.forename: Julius
authors.initials: J
authors.lastname: Oyugi
authors.affiliation: Kenya Medical Research Institute (KEMRI), Nairobi, Kenya. FOkoth@kemri.org.
authors.forename: Fredrick
authors.initials: F
authors.lastname: Okoth
authors.affiliation: Kenyatta National Hospital, Nairobi, Kenya. kiokohenrym@gmail.com.
authors.forename: Henry
authors.initials: H
authors.lastname: Kioko
authors.affiliation: Moi University and Moi Teaching and Referral Hospital, Eldoret, Kenya. smining57@gmail.com.
authors.forename: Simeon
authors.initials: S
authors.lastname: Mining
authors.affiliation: Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya. nbudambula@yahoo.com.|Present address: Embu University College, Embu, Kenya. nbudambula@yahoo.com.
authors.forename: Nancy L M
authors.initials: NL
authors.lastname: Budambula
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada. elizabeth.giles@phac-aspc.gc.ca.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Giles
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada. anton.andonov@phac-aspc.gc.ca.
authors.forename: Anton
authors.initials: A
authors.lastname: Andonov
authors.affiliation: Kenya Medical Research Institute (KEMRI), Nairobi, Kenya. ESongok@kemri.org.
authors.forename: Elijah
authors.initials: E
authors.lastname: Songok
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Canada. carla.osiowy@phac-aspc.gc.ca.
authors.forename: Carla
authors.initials: C
authors.lastname: Osiowy
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006509:Hepatitis B / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology*; D006525:Hepatitis, Viral, Human / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology; D006801:Humans; D007565:Jaundice / Q000821:virology*; D007630:Kenya / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D016036:Seroepidemiologic Studies; D055815:Young Adult