Revisiting human T-cell lymphotropic virus types 1 and 2 infections among rural population in Gabon, central Africa thirty years after the first analysis

PLoS Negl Trop Dis. 2018 Oct 25;12(10):e0006833. doi: 10.1371/journal.pntd.0006833. eCollection 2018 Oct.

Abstract

HTLV-1 infection is considered as highly endemic in central Africa. Thirty years ago, a first epidemiological study was performed in Gabon, central Africa, and revealed that the prevalence varied from 5.0 to 10.5%. To evaluate current distribution of HTLVs in Gabon, 4.381 samples were collected from rural population living in 220 villages distributed within the 9 provinces of country. HTLVs prevalence was determined using two ELISA tests and positive results were confirmed by Western Blot. The overall HTLV-1 seroprevalence was of 7.3% among the rural Gabonese population; with 5.4% for men and 9.0% for women. Prevalence of HTLV-1 differed by province, ranging from 2.3% to 12.5% into the rain forest. Being a woman older than 51 years represented a high risk for HTLV-1 acquisition. Hospitalization, operation/surgery, transfusion and medical abortion or fever, arthritis and abdominal pain are also significant risk factors. In addition, 0.1% of samples were found as HTLV-2 positive, while 12.0% had an indeterminate HTLV serological pattern. HTLV-3 and HTLV-4 were not found. Phylogenetic analysis was performed on 87 samples and demonstrated that HTLV-1 present in Gabon belongs mostly to subtype B, however the rare subtype D was also found. Altogether, our results demonstrate that almost thirty years after the first epidemiological study prevention of HTLVs infection is still an issue in Gabon.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Animals
  • Antibodies, Viral / blood
  • Blotting, Western
  • Enzyme-Linked Immunosorbent Assay
  • Gabon / epidemiology
  • HTLV-I Infections / epidemiology*
  • HTLV-II Infections / epidemiology*
  • Human T-lymphotropic virus 1 / classification
  • Human T-lymphotropic virus 1 / genetics
  • Human T-lymphotropic virus 1 / immunology
  • Human T-lymphotropic virus 2 / immunology
  • Humans
  • Male
  • Middle Aged
  • Molecular Epidemiology
  • Phylogeny
  • Risk Factors
  • Rural Population*
  • Sequence Analysis, DNA
  • Seroepidemiologic Studies
  • Surveys and Questionnaires
  • Young Adult

Substances

  • Antibodies, Viral

Grants and funding

The ‘Centre International de Recherches Medicales de Franceville’, in Franceville, Gabon, is funded by the Gabonese Government, Total Gabon and the French Foreign Ministry. The ‘Fonds de Solidarite Prioritaire’ of the French Foreign Ministry and the Global Viral Forecasting in San Francisco, USA are the funders; they had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.