title: Modeling the economic and epidemiologic impact of hookworm vaccine and mass drug administration (MDA) in Brazil, a high transmission setting.
abstract: BACKGROUND
  Although mass drug administration (MDA) has helped reduce morbidity attributed to soil-transmitted helminth infections in children, its limitations for hookworm infection have motivated the development of a human hookworm vaccine to both improve morbidity control and ultimately help block hookworm transmission leading to elimination. However, the potential economic and epidemiologic impact of a preventive vaccine has not been fully evaluated.
  
  
  METHODS
  We developed a dynamic compartment model coupled to a clinical and economics outcomes model representing both the human and hookworm populations in a high transmission region of Brazil. Experiments simulated different implementation scenarios of MDA and vaccination under varying circumstances.
  
  
  RESULTS
  Considering only intervention costs, both annual MDA and vaccination were highly cost-effective (ICERs ≤ $790/DALY averted) compared to no intervention, with vaccination resulting in lower incremental cost-effectiveness ratios (ICERs ≤ $444/DALY averted). From the societal perspective, vaccination was economically dominant (i.e., less costly and more effective) versus annual MDA in all tested scenarios, except when vaccination was less efficacious (20% efficacy, 5 year duration) and MDA coverage was 75%. Increasing the vaccine's duration of protection and efficacy, and including a booster injection in adulthood all increased the benefits of vaccination (i.e., resulted in lower hookworm prevalence, averted more disability-adjusted life years, and saved more costs). Assuming its target product profile, a pediatric hookworm vaccine drastically decreased hookworm prevalence in children to 14.6% after 20 years, compared to 57.2% with no intervention and 54.1% with MDA. The addition of a booster in adulthood further reduced the overall prevalence from 68.0% to 36.0% and nearly eliminated hookworm infection in children.
  
  
  CONCLUSIONS
  Using a human hookworm vaccine would be cost-effective and in many cases economically dominant, providing both health benefits and cost-savings. It could become a key technology in effecting control and elimination efforts for hookworm globally.
authors.affiliation: Public Health Computational and Operational Research (PHICOR), Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA; Global Obesity Prevention Center, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA.
authors.forename: Sarah M
authors.initials: SM
authors.lastname: Bartsch
authors.affiliation: National School of Tropical Medicine, and Departments of Pediatrics and Molecular Virology & Microbiology, Baylor College of Medicine, One Baylor Plaza, BCM113, Houston, TX 77030, USA; Sabin Vaccine Institute, 2000 Pennsylvania Avenue NW, Washington, DC 20006, USA.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Hotez
authors.affiliation: Public Health Computational and Operational Research (PHICOR), Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA; Global Obesity Prevention Center, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA.
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Hertenstein
authors.affiliation: Sabin Vaccine Institute, 2000 Pennsylvania Avenue NW, Washington, DC 20006, USA; Department of Microbiology, Immunology and Tropical Medicine, The George Washington University Medical Center, Washington, DC 20037, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Diemert
authors.affiliation: Public Health Computational and Operational Research (PHICOR), Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA; Global Obesity Prevention Center, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA.
authors.forename: Kristina M
authors.initials: KM
authors.lastname: Zapf
authors.affiliation: National School of Tropical Medicine, and Departments of Pediatrics and Molecular Virology & Microbiology, Baylor College of Medicine, One Baylor Plaza, BCM113, Houston, TX 77030, USA; Sabin Vaccine Institute, 2000 Pennsylvania Avenue NW, Washington, DC 20006, USA.
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Bottazzi
authors.affiliation: Sabin Vaccine Institute, 2000 Pennsylvania Avenue NW, Washington, DC 20006, USA; Department of Microbiology, Immunology and Tropical Medicine, The George Washington University Medical Center, Washington, DC 20037, USA.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Bethony
authors.affiliation: Pittsburgh Supercomputing Center, Carnegie Mellon University, 300S Craig St, Pittsburgh, PA 15213, USA.
authors.forename: Shawn T
authors.initials: ST
authors.lastname: Brown
authors.affiliation: Public Health Computational and Operational Research (PHICOR), Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA; Global Obesity Prevention Center, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA. Electronic address: brucelee@jhu.edu.
authors.forename: Bruce Y
authors.initials: BY
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000871:Anthelmintics / Q000627:therapeutic use; D001938:Brazil; D002648:Child; D002675:Child, Preschool; D003362:Cost-Benefit Analysis; D006725:Hookworm Infections / Q000188:drug therapy / Q000517:prevention & control*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D032541:Mass Vaccination / Q000191:economics*; D018803:Models, Economic; D014612:Vaccines / Q000191:economics / Q000627:therapeutic use*
chemical_list: D000871:Anthelmintics; D014612:Vaccines
keywords: Cost; Drug treatment; Economics; Hookworm; Transmission; Vaccine