Pisit Su-ArehawaratanaPreecha SingharajDavid N. TaylorCharles HogeAndrew TrofaKrit KuvanontSricharoen MigasenaPunnee PitisuttithamYu Leung LimGenevieve LosonskyJames B. KaperSteven S. WassermanStanley CryzPeter EcheverriaMyron M. LevineMahidol UniversityWalter Reed Army Institute of ResearchUniversity of Maryland School of MedicineBerna Biotech AG2018-08-102018-08-101992-01-01Journal of Infectious Diseases. Vol.165, No.6 (1992), 1042-104815376613002218992-s2.0-0026596515https://repository.li.mahidol.ac.th/handle/20.500.14594/22501Attenuated Vibrio cholerae oral vaccine CVD 103-HgR was well tolerated by 324 Thai soldiers and civilians. Most received a single 5 × 10(r) cfu dose, while 40 each received one or two 5 × 109cfu doses. Vibriocidal antibody (the best correlate of immunity) seroconversion was lower in soldiers than civilians (P <.001). Increasing the vaccine dose to 5 × 109cfu raised the geometric mean titer (P <.001). A second 5 × 109cfu dose one week later did not notably increase serocon- versions. Likelihood of seroconversion was inversely correlated with baseline vibriocidal titer (P <.001). CVD 103-HgR caused seroconversion in most subjects with baseline titers <1:40, including 100% of civilians after one 5 × 10(r) cfu dose, 79% of soldiers after one 5 × 109cfu dose, and 45% of soldiers after one 5 × 10scfu dose. In persons with elevated baseline titers, vibriocidal antibody seroconversion is not a sensitive measure of whether vaccine has boosted intestinal immunity; for such subjects, other measurements must be used. Study regimens in endemic areas should use a single 5 × 109cfu dose. © 1992 The University of Chicago.Mahidol UniversityMedicineArticleSCOPUS10.1093/infdis/165.6.1042