title: Two-year study of the protective efficacy of the oral whole cell plus recombinant B subunit cholera vaccine in Peru.
abstract: The protective efficacy of an oral inactivated whole cell Vibrio cholerae plus recombinant B subunit cholera vaccine was determined against El Tor cholera among Peruvian children and adults (2-65 years old) in a randomized, double-blind manner. Study subjects received 2 doses of vaccine or placebo 2 weeks apart, followed by a booster dose 10 months later. Surveillance for cholera was performed actively, with 2 visits per week to each household, and passively, at a local hospital. Stool samples were collected during diarrhea episodes and were cultured for V. cholerae. A total of 17,799 persons received 2 doses of vaccine or placebo, and 14,997 of these persons received the booster dose. After 2 doses (first surveillance period), V. cholerae biotype O1 was isolated from 17 vaccinees and 16 placebo recipients, demonstrating vaccine efficacy (VE) of -4%. After 3 doses (second surveillance period), V. cholerae O1 was isolated from 13 vaccinees and 32 placebo recipients, demonstrating VE of 61% (95% confidence interval ¿CI, 28%-79%). In the second surveillance period, the VE for illness requiring hospitalization was 82% (95% CI, 27%-96%). VE was also higher for persons >15 years old (VE, 72%; 95% CI, 28%-89%).
authors.affiliation: Dept. of Enteric Infections, Division of Communicable Diseases and Immunology, Walter Reed Army Institute of Research, Washington, DC 20307-5100, USA. David.Taylor@na.amedd.army.mil.
authors.forename: D N
authors.initials: DN
authors.lastname: Taylor
authors.forename: V
authors.initials: V
authors.lastname: Cárdenas
authors.forename: J L
authors.initials: JL
authors.lastname: Sanchez
authors.forename: R E
authors.initials: RE
authors.lastname: Bégué
authors.forename: R
authors.initials: R
authors.lastname: Gilman
authors.forename: C
authors.initials: C
authors.lastname: Bautista
authors.forename: J
authors.initials: J
authors.lastname: Perez
authors.forename: R
authors.initials: R
authors.lastname: Puga
authors.forename: A
authors.initials: A
authors.lastname: Gaillour
authors.forename: R
authors.initials: R
authors.lastname: Meza
authors.forename: P
authors.initials: P
authors.lastname: Echeverria
authors.forename: J
authors.initials: J
authors.lastname: Sadoff
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D002771:Cholera / Q000453:epidemiology / Q000276:immunology* / Q000517:prevention & control*; D002772:Cholera Toxin / Q000008:administration & dosage / Q000276:immunology*; D022121:Cholera Vaccines / Q000008:administration & dosage; D003967:Diarrhea / Q000821:virology; D005243:Feces / Q000382:microbiology; D006801:Humans; D008875:Middle Aged; D010568:Peru / Q000453:epidemiology; D011159:Population Surveillance; D014614:Vaccines, Synthetic / Q000008:administration & dosage*; D014734:Vibrio cholerae / Q000276:immunology / Q000302:isolation & purification; D017201:Virus Shedding
chemical_list: D022121:Cholera Vaccines; D014614:Vaccines, Synthetic; D002772:Cholera Toxin