The impact of vaccination and prior exposure on stool shedding of salmonella typhi and salmonella paratyphi in 6 controlled human infection studies
JournalClinical Infectious Diseases
PublisherOxford University Press
MetadataShow full item record
AbstractBackground Shedding of Salmonella Typhi or Paratyphi in the stool or urine leads to contamination of food or water, which is a prerequisite for transmission of enteric fever. Currently, there are limited data on the effect of vaccination or prior exposure on stool shedding. Methods Six Salmonella Typhi or Paratyphi human challenge studies were conducted between 2011 and 2017. Participants were either unvaccinated or vaccinated with 1 of 4 vaccines: Vi-polysaccharide (Vi-PS), Vi-tetanus-toxoid conjugate vaccine (Vi-TT), live oral Ty21a vaccine, or an experimental vaccine (M01ZH09). Daily stool cultures were collected for 14 days after challenge. Results There were 4934 stool samples collected from 430 volunteers. Participants who received Vi-PS or Vi-TT shed less than unvaccinated participants (odds ratio [OR], 0.34; 95% confidence interval [CI], 0.15-0.77; P =.010 and OR, 0.41; 95% CI, 0.19-0.91, P =.029 for Vi-PS and Vi-TT, respectively). Higher anti-Vi immunoglobulin G titers were associated with less shedding of S. Typhi (P <.0001). A nonsignificant reduction in shedding was associated with Ty21a vaccine (OR, 0.57; 95% CI, 0.27-1.20; P =.140). Individuals previously exposed to S. Typhi shed less than previously unexposed individuals (OR, 0.30; 95% CI, 0.1-0.8; P =.016). Shedding of S. Typhi was more common than S. Paratyphi. Conclusions Prior vaccination with Vi vaccines, or natural infection, reduces onward transmission of S. Typhi. Field trials of Vi-TT should be designed to detect indirect protection, reflecting the consequence of reduced stool shedding observed in the human challenge model. © 2018 The Author(s).
SponsorsSee funder listing in the publication.
typhoid conjugate vaccine
Identifier to cite or link to this itemhttps://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85064110859&origin=inward; http://hdl.handle.net/10713/10076
- Specific and cross-reactive immune response to oral Salmonella Typhi Ty21a and parenteral Vi capsular polysaccharide typhoid vaccines administered concomitantly.
- Authors: Pakkanen SH, Kantele JM, Savolainen LE, Rombo L, Kantele A
- Issue date: 2015 Jan 9
- Efficacy and immunogenicity of a Vi-tetanus toxoid conjugate vaccine in the prevention of typhoid fever using a controlled human infection model of Salmonella Typhi: a randomised controlled, phase 2b trial.
- Authors: Jin C, Gibani MM, Moore M, Juel HB, Jones E, Meiring J, Harris V, Gardner J, Nebykova A, Kerridge SA, Hill J, Thomaides-Brears H, Blohmke CJ, Yu LM, Angus B, Pollard AJ
- Issue date: 2017 Dec 2
- Vi Capsular Polysaccharide Produced by Recombinant <i>Salmonella enterica</i> Serovar Paratyphi A Confers Immunoprotection against Infection by <i>Salmonella enterica</i> Serovar Typhi.
- Authors: Xiong K, Zhu C, Chen Z, Zheng C, Tan Y, Rao X, Cong Y
- Issue date: 2017
- Enteric fever in Israeli travelers: a nationwide study.
- Authors: Meltzer E, Sadik C, Schwartz E
- Issue date: 2005 Sep-Oct
- Vaccines for preventing typhoid fever.
- Authors: Milligan R, Paul M, Richardson M, Neuberger A
- Issue date: 2018 May 31