title: Impact of different dosing schedules on the immunogenicity of the human rotavirus vaccine in infants in Pakistan: a randomized trial.
abstract: BACKGROUND
  Current oral rotavirus vaccines perform suboptimally in resource-poor settings. We investigated the effect of an additional dose and later schedule on the immunogenicity of monovalent rotavirus vaccine (RV1) in a developing country.
  
  
  METHODS
  Infants received RV1 at 6 and 10, 10 and 14, or 6, 10, and 14 weeks of age. The primary objective was to compare antirotavirus immunoglobulin A (IgA) seroconversion at 18 weeks in the 6/10/14 arm to the cumulative seroconversion (highest result at 14 or 18 weeks) in the 6/10 arm.
  
  
  RESULTS
  Overall, 480 (76.2%) of 630 randomized infants completed the trial per protocol. Seroconversion in the 6/10/14 arm was 36.7% (95% CI, 29.8, 44.2) compared to 36.1% (CI, 29.0, 43.9) in the 6/10 arm, (P=1.0); the result from the 10/14 arm was 38.5% (CI, 31.2, 46.3). Seroconversion in the 6/10 arm at 14 weeks (post hoc) was lower at 29.7% (CI, 23.1, 37.3).
  
  
  CONCLUSIONS
  In Pakistani infants, the immunogenicity of RV1 did not increase significantly with 3 doses at 6, 10, and 14 weeks compared to 2 doses at 6 and 10 weeks. Additional strategies should be evaluated for improving rotavirus vaccine immunogenicity in high burden countries.
authors.affiliation: Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan.
authors.forename: Syed Asad
authors.initials: SA
authors.lastname: Ali
authors.affiliation: Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan.
authors.forename: Abdul Momin
authors.initials: AM
authors.lastname: Kazi
authors.affiliation: Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Margaret M
authors.initials: MM
authors.lastname: Cortese
authors.affiliation: Vaccine Access and Delivery, Program for Appropriate Technology in Health (PATH), Seattle, Washington.
authors.forename: Jessica A
authors.initials: JA
authors.lastname: Fleming
authors.affiliation: Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Umesh D
authors.initials: UD
authors.lastname: Parashar
authors.affiliation: Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Baoming
authors.initials: B
authors.lastname: Jiang
authors.affiliation: Department of Pediatrics, Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, Ohio.
authors.forename: Monica Malone
authors.initials: MM
authors.lastname: McNeal
authors.affiliation: Vaccine Access and Delivery, Program for Appropriate Technology in Health (PATH), Seattle, Washington Now With The Bill & Melinda Gates Foundation, Seattle, Washington.
authors.forename: Duncan
authors.initials: D
authors.lastname: Steele
authors.affiliation: Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan.
authors.forename: Zulfiqar
authors.initials: Z
authors.lastname: Bhutta
authors.affiliation: Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan.
authors.forename: Anita
authors.initials: A
authors.lastname: Zaidi
mesh_terms: D057134:Antibodies, Neutralizing / Q000097:blood / Q000276:immunology; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007115:Immunization Schedule; D007070:Immunoglobulin A / Q000097:blood / Q000276:immunology; D007223:Infant; D008297:Male; D017063:Outcome Assessment, Health Care; D010154:Pakistan; D012401:Rotavirus / Q000276:immunology*; D012400:Rotavirus Infections / Q000517:prevention & control*; D022243:Rotavirus Vaccines / Q000008:administration & dosage* / Q000009:adverse effects / Q000276:immunology*
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D007070:Immunoglobulin A; D022243:Rotavirus Vaccines
keywords: Pakistan; Rotarix; rotavirus; rotavirus vaccine; vaccination schedule