SAFETY, IMMUNOGENICITY, AND TRANSMISSIBILITY OF SINGLE-DOSE LIVE ORALCHOLERA VACCINE STRAIN CVD-103-HGR IN 24-MONTH-OLD TO 59-MONTH-OLD INDONESIAN CHILDREN

Recombinant A-B+ Vibrio cholerae 01 strain CVD 103-HgR is a safe, high ly immunogenic, single-dose live oral vaccine in adults in industriali zed countries. Safety, excretion, immunogenicity, vaccine transmissibi lity, and environmental introduction of CVD 103-HgR were investigated among 24- to 59-month-old children in Jakarta. In 81 households, I chi ld was randomly allocated a single dose of vaccine (5 x 10(9) cfu) and another, placebo. Additionally, 139 unpaired children were randomly a llocated vaccine or placebo. During 9 days of follow-up, diarrhea or v omiting did not occur more often among vaccinees than controls. Vaccin e was minimally excreted and was isolated from no controls and from 1 (0.6%) of 177 unvaccinated family contacts. A 4-fold or higher rise in serum vibriocidal antibody was observed in 75% of vaccinees (10-fold rise in geometric mean titer over baseline). Of 135 paired placebo rec ipients or household contacts, 5 had vibriocidal seroconversions. Moor e swabs placed in sewers and latrines near 97 households failed to det ect vaccine. These observations pave the way for a large-scale field t rial of efficacy.