The Spectrum of Cholera in Rural East I. Correlation of Bacteriologic and Serologic Results

A group of 107 children was studied intensely throughout the course of a large epidemic of cholera in 1 village of East Pakistan. The overall rate of infection was 18.7%, and infection rates decreased with increasing age. The ratio of nonhospitalized to hospitalized infections was 5:1. The percentage of detectable titers of vibriocidal antibody in blood specimens obtained before the epidemic increased markedly with age, while that of toxin-neutralization antibody titers declined slightly. Detectable, initial vibriocidal titers were associated with a lower rate of infection than were undetectable titers. The situation was reversed with regard to toxin-neutralization levels, although the presence of detectable titers tended to be associated with milder disease. All 20 infections were discovered by daily rectal swab cultures, while a 4-fold increase in vibriocidal titer was present in only 12 of these individuals, and an absolute rise of 20 or more antitoxin units/ml was present in 10. The duration of excretion of vibrios was significantly less in individuals who did not convert serologically.