Immune responses to cholera following natural infection: a review

Abstract

AbstractCholera is an acute, diarrheal disease caused by Vibrio cholerae O1 or 139 that is associated with a high global burden. In this review, we identify the estimated duration of immunity following cholera infection with and without clinical symptoms from available published studies. We searched Pubmed and Web of Science for studies examining the long-term infection-acquired immunity against cholera infection. We identified 22 eligible studies and categorized them as either observational, challenge, or serological. We observed in observational and challenge studies that at three years, there is strong evidence of protection. However, serological studies show that elevated humoral markers returned to baseline within one year. Although with small sample sizes, three studies found that most participants with a subclinical infection from an initial challenge with cholera had a symptomatic infection when rechallenged with a homologous biotype, suggesting that a subclinical cholera infection may confer lower protection than a clinical one. This review underscores the need to elucidate potential differences in the protection provided by clinical and subclinical cholera infections. Further, more studies are warranted to bridge the gap between the correlates of protection and cholera immunity. Understanding the duration of natural immunity to cholera can help guide control strategies and policy.