title: Cost-effectiveness of community-based screening and treatment for chronic hepatitis B in The Gambia: an economic modelling analysis.
abstract: Despite the high burden of hepatitis B virus (HBV) infection in sub-Saharan Africa, absence of widespread screening and poor access to treatment leads to most people remaining undiagnosed until later stages of disease when prognosis is poor and treatment options are limited. We examined the cost-effectiveness of community-based screening and early treatment with antiviral therapy for HBV in The Gambia.
  
  
  
  In this economic evaluation, we combined a decision tree with a Markov state transition model to compare a screen and treat intervention consisting of adult community-based screening using a hepatitis B surface antigen (HBsAg) rapid test and subsequent HBV antiviral therapy versus current practice, in which there is an absence of publicly provided screening or treatment for HBV. We used data from the PROLIFICA study to parameterise epidemiological, primary screening, and cost information, and other model parameter inputs were obtained from a literature search. Outcome measures were cost per disability-adjusted life-year (DALY) averted; cost per life-year saved; and cost per quality-adjusted life-year (QALY) gained. We calculated the incremental cost-effectiveness ratios (ICERs) between current practice and the screen and treat intervention. Costs were assessed from a health provider perspective. Costs (expressed in 2013 US$) and health outcomes were discounted at 3% per year.
  
  
  
  In The Gambia, where the prevalence of HBsAg is 8·8% in people older than 30 years, adult screening and treatment for HBV has an incremental cost-effectiveness ratio (ICER) of $540 per DALY averted, $645 per life-year saved, and $511 per QALY gained, compared with current practice. These ICERs are in line with willingness-to-pay levels of one times the country's gross domestic product per capita ($487) per DALY averted, and remain robust over a wide range of epidemiological and cost parameter inputs.
  
  
  
  Adult community-based screening and treatment for HBV in The Gambia is likely to be a cost-effective intervention. Higher cost-effectiveness might be achievable with targeted facility-based screening, price reductions of drugs and diagnostics, and integration of HBV screening with other public health interventions.
  
  
  
  European Commission.
authors.affiliation: Division of Digestive Diseases, St Mary's Hospital, Imperial College, London, UK; Department of Infectious Disease Epidemiology, School of Public Health, Imperial College, London, UK. Electronic address: s.nayagam01@imperial.ac.uk.
authors.forename: Shevanthi
authors.initials: S
authors.lastname: Nayagam
authors.affiliation: Health Economics Group, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College, London, UK.
authors.forename: Lesong
authors.initials: L
authors.lastname: Conteh
authors.affiliation: Health Economics Group, Department of Infectious Disease Epidemiology, School of Public Health, Imperial College, London, UK; ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clinic, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Elisa
authors.initials: E
authors.lastname: Sicuri
authors.affiliation: Medical Research Council Laboratories, The Gambia Unit, Fajara, The Gambia; Unité d'Épidémiologie des Maladies Émergentes, Institut Pasteur, Paris, France.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Shimakawa
authors.affiliation: Medical Research Council Laboratories, The Gambia Unit, Fajara, The Gambia.
authors.forename: Penda
authors.initials: P
authors.lastname: Suso
authors.affiliation: Medical Research Council Laboratories, The Gambia Unit, Fajara, The Gambia.
authors.forename: Saydiba
authors.initials: S
authors.lastname: Tamba
authors.affiliation: International Agency for Research on Cancer (IARC), Lyon, France.
authors.forename: Ramou
authors.initials: R
authors.lastname: Njie
authors.affiliation: Medical Research Council Laboratories, The Gambia Unit, Fajara, The Gambia.
authors.forename: Harr
authors.initials: H
authors.lastname: Njai
authors.affiliation: Division of Digestive Diseases, St Mary's Hospital, Imperial College, London, UK; Medical Research Council Laboratories, The Gambia Unit, Fajara, The Gambia.
authors.forename: Maud
authors.initials: M
authors.lastname: Lemoine
authors.affiliation: Department of Infectious Disease Epidemiology, School of Public Health, Imperial College, London, UK.
authors.forename: Timothy B
authors.initials: TB
authors.lastname: Hallett
authors.affiliation: Division of Digestive Diseases, St Mary's Hospital, Imperial College, London, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: Thursz
mesh_terms: D000328:Adult; D000998:Antiviral Agents / Q000191:economics* / Q000627:therapeutic use; D003362:Cost-Benefit Analysis / Q000191:economics*; D005260:Female; D005714:Gambia; D006509:Hepatitis B / Q000175:diagnosis* / Q000188:drug therapy; D006514:Hepatitis B Surface Antigens / Q000097:blood; D006515:Hepatitis B virus / Q000276:immunology; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods; D018803:Models, Economic; D019095:Point-of-Care Systems; D019057:Quality-Adjusted Life Years
chemical_list: D000998:Antiviral Agents; D006514:Hepatitis B Surface Antigens