Safety, Immunogenicity and Lot Stability of the Whole Cell/Recombinant B Subunit (WC/rCTB) Cholera Vaccine in Peruvian Adults and Children
Abstract
To assess the safety, immunogenicity, and lot stability of the whole cell/recombinant B subunit cholera vaccine, 2 lots manufactured in June 1991 and February 1992 were tested in January 1995. Two oral doses of vaccine or placebo given 2 weeks apart were given with buffer to 216 Peruvian adults and children. Symptoms were elicited for 3 days after each dose. Serum and plasma specimens obtained from each volunteer before vaccination and 10- 14 days after the second dose were tested for vibriocidal and anti-cholera toxin antibodies. The vaccine was well- tolerated. Nearly half of the 100 vaccines had pre-vaccination vibriocidal titers greater than 1:40. Elevated titers were observed in 22% of 37 children 2-5 years of age compared with 66% of 63 vaccines 6-65 years (P < 0.001) A greater than =2-fold serum vibriocidal response was observed in 55% of 100 vaccines and 6% of 32 placebo recipients. An elevated pre- vaccination titer (greater than 1:40) did not change the proportion of vaccines who responded with a greater than 2-fold increase in vibriocidal titer (51% versus 59%, difference not significant), but did change the proportion responding with a greater than =- fold increase (41% versus 22%; P < 0.05). The vibriocidal seroconversion rate was lowest in children 2-5 years old despite low pre-vaccination titers. Two-fold or greater serum antitoxic responses in IgA and IgG were observed in >90% of the vaccinees %4-fold responses were seen in 65-70% of the vaccinees with a 6-8-fold increase over baseline. Plasma specimens were as good as sera for determining anti-toxic antibodies by ELISA, but were less satisfactory for determining vibriocidal antibody titers.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1999
- Accession Number
- ADA379283
Entities
People
- Ann-mari Svennerholm
- David N. Taylor
- Juan Perez
- Romulo Puga
- Vicky Cardenas
Organizations
- Naval Medical Research Center