title: Cost-effectiveness of a potential group B streptococcal vaccine program for pregnant women in South Africa.
abstract: BACKGROUND
  In low- and middle-income countries neonatal infections are important causes of infant mortality. Group B streptococcus (GBS) is a major pathogen. A GBS polysaccharide-protein conjugate vaccine, the only option that has the potential to prevent both early- and late-onset GBS disease, has completed Phase II trials. Screening-based intrapartum antibiotic prophylaxis (IAP) for pregnant women, an effective strategy in high-income countries, is often not practical in these settings. Risk factor-based IAP (RFB-IAP) for women with risk factors at delivery has had limited success in preventing neonatal infection. We evaluated the cost and health impacts of maternal GBS vaccination in South Africa.
  
  
  RESULTS
  We developed a decision-analytic model for an annual cohort of pregnant women that simulates the natural history of GBS disease in their infants. We compared four strategies: doing nothing, maternal GBS vaccination, RFB-IAP, and vaccination plus RFB-IAP. Assuming vaccine efficacy varies from 50% to 90% against covered serotypes and 75% of pregnant women are vaccinated, GBS vaccination alone prevents 30-54% of infant GBS cases compared to doing nothing. For vaccine prices between $10 and $30, and mid-range efficacy, its cost ranges from $676 to $2390 per disability-adjusted life-year (DALY) averted ($US 2010), compared to doing nothing. RFB-IAP alone, compared to doing nothing, prevents 10% of infant GBS cases at a cost of $240/DALY. Vaccine plus RFB-IAP prevents 48% of cases at a cost of $664-2128/DALY.
  
  
  CONCLUSIONS
  Vaccination would substantially reduce the burden of infant GBS disease in South Africa and would be very cost-effective by WHO guidelines. RFB-IAP is also very cost-effective, but prevents only 10% of cases. Vaccination plus RFB-IAP is more effective and more costly than vaccination alone, and consistently very cost-effective.
authors: Division of Management, Policy and Community Health, University of Texas School of Public Health, San Antonio, TX, USA. Electronic address: Sun-Young.Kim@uth.tmc.edu.
authors: Sun-Young
authors: SY
authors: Kim
authors: Institute for Health, Health Care Policy, and Aging Research, and Department of Economics, Rutgers University, New Brunswick, NJ, USA.
authors: Louise B
authors: LB
authors: Russell
authors: Institute for Health, Health Care Policy, and Aging Research, and Department of Economics, Rutgers University, New Brunswick, NJ, USA.
authors: Jeehyun
authors: J
authors: Park
authors: National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
authors: Jennifer R
authors: JR
authors: Verani
authors: Medical Research Council: Respiratory and Meningeal Pathogens Research Unit and Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa.
authors: Shabir A
authors: SA
authors: Madhi
authors: Medical Research Council: Respiratory and Meningeal Pathogens Research Unit and Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa.
authors: Clare L
authors: CL
authors: Cutland
authors: National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
authors: Stephanie J
authors: SJ
authors: Schrag
authors: Department of Preventive Medicine and Community Health, New Jersey Medical School, Rutgers University, Newark, NJ, USA.
authors: Anushua
authors: A
authors: Sinha
mesh_terms: D019072:Antibiotic Prophylaxis / Q000191:economics; D003362:Cost-Benefit Analysis; D005260:Female; D006801:Humans; D018445:Infectious Disease Transmission, Vertical / Q000191:economics / Q000517:prevention & control*; D018803:Models, Economic; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000191:economics / Q000517:prevention & control*; D012307:Risk Factors; D013019:South Africa; D013290:Streptococcal Infections / Q000191:economics / Q000517:prevention & control*; D022541:Streptococcal Vaccines / Q000191:economics* / Q000627:therapeutic use; D013292:Streptococcus agalactiae; D014611:Vaccination / Q000191:economics*
chemical_list: D022541:Streptococcal Vaccines
keywords: Cost-effectiveness; GBS vaccine; Group B streptococcal (GBS); Intrapartum antibiotic prophylaxis (IAP); Neonatal sepsis; South Africa