title: Hepatitis C virus infections in the Democratic Republic of Congo exhibit a cohort effect.
abstract: The prevalence and genetic diversity of hepatitis C virus (HCV) and human pegivirus (HPgV) in many regions of sub-Saharan Africa is poorly characterized, including in the Democratic Republic of Congo--the largest country in the region and one of the most populous. To address this situation we conducted a molecular epidemiological survey of HCV and HPgV (previously named GB Virus C or hepatitis G virus) in samples collected in 2007 from 299 males from the DRC, whose ages ranged from 21 to 71 years old. Samples were tested for the presence of HCV antibodies by ELISA and reactive samples were subsequently tested for HCV RNA using RT-PCR in which both the HCV Core and NS5B genome regions were amplified. Remaining samples were tested for HPgV RNA and the HPgV NS3 genome region of positive samples was amplified. For HCV, 13.7% of the samples were seropositive (41/299) but only 3.7% were viremic (11/299). HPgV RNA was found in 12.7% (33/259) of samples. HCV viremia was strongly associated with age; the percentage of samples that contained detectable HCV RNA was ~0.5% in those younger than 50 and 13% in those older than 50. Our study represents the first systematic survey of HCV genetic diversity in the DRC. HCV sequences obtained belonged to diverse lineages of genotype 4, including subtypes 4c, 4 k, 4 l and 4r, plus one unclassified lineage that may constitute a new subtype. These data suggest that HCV in the DRC exhibits an age 'cohort effect', as has been recently reported in neighbouring countries, and are consistent with the hypothesis that HCV transmission rates were higher in the mid-twentieth century, possibly as a result of parenteral, iatrogenic, or other unidentified factors. Different HCV subtypes were associated with individuals of different ages, implying that HCV infection in the DRC may have arisen through multiple separate HCV epidemics with different causes.
authors: Department of Zoology, University of Oxford, South Parks Road, Oxford, UK.
authors: James C
authors: JC
authors: Iles
authors: G L
authors: GL
authors: Abby Harrison
authors: Sinead
authors: S
authors: Lyons
authors: Cyrille F
authors: CF
authors: Djoko
authors: Ubald
authors: U
authors: Tamoufe
authors: Matthew
authors: M
authors: Lebreton
authors: Bradley S
authors: BS
authors: Schneider
authors: Joseph N
authors: JN
authors: Fair
authors: Felix M
authors: FM
authors: Tshala
authors: Patrick K
authors: PK
authors: Kayembe
authors: Jean Jacques
authors: JJ
authors: Muyembe
authors: Samuel
authors: S
authors: Edidi-Basepeo
authors: Nathan D
authors: ND
authors: Wolfe
authors: Paul
authors: P
authors: Klenerman
authors: Peter
authors: P
authors: Simmonds
authors: Oliver G
authors: OG
authors: Pybus
mesh_terms: D000328:Adult; D000368:Aged; D015988:Cohort Effect; D015023:Democratic Republic of the Congo / Q000453:epidemiology; D018067:Flaviviridae; D018178:Flaviviridae Infections; D016174:Hepacivirus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D006526:Hepatitis C / Q000453:epidemiology* / Q000821:virology; D018937:Hepatitis C Antibodies / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D010802:Phylogeny; D055815:Young Adult
chemical_list: D018937:Hepatitis C Antibodies
keywords: Democratic Republic of Congo; Hepatitis C; Human pegivirus; Phylogeny; Prevalence; RNA