Immunogenicity of a killed bivalent (O1 and O139) whole cell oral cholera vaccine, Shanchol, in Haiti.
BACKGROUND
Studies of the immunogenicity of the killed bivalent whole cell oral cholera vaccine, Shanchol, have been performed in historically cholera-endemic areas of Asia. There is a need to assess the immunogenicity of the vaccine in Haiti and other populations without historical exposure to Vibrio cholerae.


RESULTS
We measured immune responses after administration of Shanchol, in 25 adults, 51 older children (6-17 years), and 47 younger children (1-5 years) in Haiti, where cholera was introduced in 2010. A≥4-fold increase in vibriocidal antibody titer against V. cholerae O1 Ogawa was observed in 91% of adults, 74% of older children, and 73% of younger children after two doses of Shanchol; similar responses were observed against the Inaba serotype. A≥2-fold increase in serum O-antigen specific polysaccharide IgA antibody levels against V. cholerae O1 Ogawa was observed in 59% of adults, 45% of older children, and 61% of younger children; similar responses were observed against the Inaba serotype. We compared immune responses in Haitian individuals with age- and blood group-matched individuals from Bangladesh, a historically cholera-endemic area. The geometric mean vibriocidal titers after the first dose of vaccine were lower in Haitian than in Bangladeshi vaccinees. However, the mean vibriocidal titers did not differ between the two groups after the second dose of the vaccine.


CONCLUSIONS
A killed bivalent whole cell oral cholera vaccine, Shanchol, is highly immunogenic in Haitian adults and children. A two-dose regimen may be important in Haiti, and other populations lacking previous repeated exposures to V. cholerae.
Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America; Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America.
Richelle C
RC
Charles
Partners In Health, Boston, Massachusetts, United States of America.
Isabelle J
IJ
Hilaire
Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America.
Leslie M
LM
Mayo-Smith
Partners In Health, Boston, Massachusetts, United States of America; Division of Global Health Equity, Brigham and Women's Hospital, Boston, Massachusetts, United States of America.
Jessica E
JE
Teng
Partners In Health, Boston, Massachusetts, United States of America.
J Gregory
JG
Jerome
Partners In Health, Boston, Massachusetts, United States of America; Department of Global Health and Social Medicine, Harvard Medical School, Boston, Massachusetts, United States of America.
Molly F
MF
Franke
International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh.
Amit
A
Saha
Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America.
Yanan
Y
Yu
National Institute of Diabetes and Digestive and Kidney Diseases, Laboratory of Bioorganic Chemistry, National Institutes of Health, Bethesda, Maryland, United States of America.
Paul
P
Kováč
Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America; Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America; Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, United States of America.
Stephen B
SB
Calderwood
Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America; Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America; Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America.
Edward T
ET
Ryan
Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America; Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America.
Regina C
RC
LaRocque
Partners In Health, Boston, Massachusetts, United States of America.
Charles P
CP
Almazor
International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh.
Firdausi
F
Qadri
Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America; Partners In Health, Boston, Massachusetts, United States of America; Division of Global Health Equity, Brigham and Women's Hospital, Boston, Massachusetts, United States of America; Department of Global Health and Social Medicine, Harvard Medical School, Boston, Massachusetts, United States of America.
Louise C
LC
Ivers
Division of Infectious Diseases, Massachusetts General Hospital, Boston, Massachusetts, United States of America; Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America.
Jason B
JB
Harris
D000293:Adolescent; D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood; D058491:Bacterial Load / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D002771:Cholera / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D022121:Cholera Vaccines / Q000008:administration & dosage / Q000276:immunology*; D058872:Epidemics; D005260:Female; D006205:Haiti; D006801:Humans; D007223:Infant; D008297:Male; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000276:immunology; D041241:Vibrio cholerae O1 / Q000276:immunology*; D041242:Vibrio cholerae O139 / Q000276:immunology*; D055815:Young Adult
D000907:Antibodies, Bacterial; D022121:Cholera Vaccines; D015164:Vaccines, Inactivated