Efficacy trial of single-dose live oral cholera vaccine CVD 103-HgR in North Jakarta, Indonesia, a cholera-endemic area

A randomized, double-blind, placebo-controlled efficacy trial of one dose o f CVD 103-HgR live oral cholera vaccine was performed in Indonesia from 199 3 to 1997. 67,508 persons aged 2-41 years ingested vaccine or placebo and w ere followed for four years, detecting cholera cases using hospital-based s urveillance. A nested reactogenicity study (538 vaccinees, 535 controls) re vealed no vaccine-attributable side effects. A nested immunogenicity study (N = 657) showed vibriocidal seroresponses in 64-70% of vaccinees vs 1-2% o f controls. Cholera incidence was lower than expected. 103 cases of Vibrio cholerae O1 El Tor diarrhea were detected, 93 evaluable for vaccine efficac y (43 vaccine, 50 placebo; efficacy=14%). A suggestion of protection was ob served among persons with blood group O [P = 0.12]. Only seven cases occurr ed within six months of vaccination, precluding assessment of short-term ef ficacy. In Jakarta, single-dose CVD 103-HgR did not confer long-term protec tion. Short-term protection from a single-dose and long-term protection fro m two doses have yet to be studied. (C) 2000 Elsevier Science Ltd. All righ ts reserved.