TY - JOUR
T1 - Protection conferred by typhoid fever against recurrent typhoid fever in urban kolkata
AU - Im, Justin
AU - Islam, Md Taufiqul
AU - Kim, Deok Ryun
AU - Ahmmed, Faisal
AU - Chon, Yun
AU - Zaman, K.
AU - Khan, Ashraful Islam
AU - Ali, Mohammad
AU - Sur, Dipika
AU - Kanungo, Suman
AU - Dutta, Shanta
AU - Bhattacharya, Sujit K.
AU - Dougan, Gordon
AU - Holt, Kathryn E.
AU - Marks, Florian
AU - Kim, Jerome H.
AU - Qadri, Firdausi
AU - Clemens, John D.
N1 - Funding Information:
The research was supported by the Diseases of the Most Impoverished Program of the Bill & Melinda Gates Foundation. This publication was made possible through a grant from the Bill & Melinda Gates Foundation (OPP1171432) awarded to JC. GD was supported by Wellcome. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Publisher Copyright:
© 2020 Im et al.
PY - 2020/8
Y1 - 2020/8
N2 - We evaluated the protection conferred by a first documented visit for clinical care of typhoid fever against recurrent typhoid fever prompting a visit. This study takes advantage of multi-year follow-up of a population with endemic typhoid participating in a cluster-randomized control trial of Vi capsular polysaccharide typhoid vaccine in Kolkata, India. A population of 70,566 individuals, of whom 37,673 were vaccinated with one dose of either Vi vaccine or a control (Hepatitis A) vaccine, were observed for four years. Surveillance detected 315 first typhoid visits, among whom 4 developed subsequent typhoid, 3 due to reinfection, defined using genomic criteria and corresponding to-124% (95% CI:-599, 28) protection by the initial illness. Point estimates of protection conferred by an initial illness were negative or negli-gible in both vaccinated and non-vaccinated subjects, though confidence intervals around the point estimates were wide. These data provide little support for a protective immunizing effect of clinically treated typhoid illness, though modest levels of protection cannot be excluded.
AB - We evaluated the protection conferred by a first documented visit for clinical care of typhoid fever against recurrent typhoid fever prompting a visit. This study takes advantage of multi-year follow-up of a population with endemic typhoid participating in a cluster-randomized control trial of Vi capsular polysaccharide typhoid vaccine in Kolkata, India. A population of 70,566 individuals, of whom 37,673 were vaccinated with one dose of either Vi vaccine or a control (Hepatitis A) vaccine, were observed for four years. Surveillance detected 315 first typhoid visits, among whom 4 developed subsequent typhoid, 3 due to reinfection, defined using genomic criteria and corresponding to-124% (95% CI:-599, 28) protection by the initial illness. Point estimates of protection conferred by an initial illness were negative or negli-gible in both vaccinated and non-vaccinated subjects, though confidence intervals around the point estimates were wide. These data provide little support for a protective immunizing effect of clinically treated typhoid illness, though modest levels of protection cannot be excluded.
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U2 - 10.1371/journal.pntd.0008530
DO - 10.1371/journal.pntd.0008530
M3 - Article
C2 - 32804950
AN - SCOPUS:85089555637
SN - 1935-2727
VL - 14
SP - 1
EP - 11
JO - PLoS neglected tropical diseases
JF - PLoS neglected tropical diseases
IS - 8
M1 - e0008530
ER -