Clinical Trial: Evaluation of the Vi Polysaccharide Vaccine Against Typhoid Fever

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Randomized Controlled Evaluation of the Vi Polysaccharide Vaccine Against Typhoid Fever in Eastern Kolkata, West Bengal, India

Brief Summary: This study is part of the International Vaccine Institute's (IVI's) typhoid Vi demonstration project that aims to accelerate the rational introduction of Vi vaccines in typhoid endemic countries. The purpose of this study is to determine the effectiveness of the Vi vaccine following a mass typhoid immunization campaign in an endemic area in Kolkata, India. The cost-effectiveness of the Vi vaccination and the logistic feasibility of a mass typhoid immunization campaign will also be evaluated.

Detailed Summary:

Typhoid fever is a major cause of morbidity worldwide. The disease predominantly affects school-aged children, is more prevalent in urban areas, may last for several weeks and can lead to serious complications. Management of this disease is further complicated by the emergence of multi-drug resistant strains. Vaccination of high risk populations is considered the most promising strategy for the control of typhoid fever. The Vi polysaccharide vaccine has been targeted for accelerated introduction into public health programs since it has been shown to have consistent efficacy results even in areas of high typhoid incidence, is given as a single dose, lacks patent protection and requires less strict cold chain requirements.

This project attempts to evaluate a new vaccination strategy for residents of endemic areas. A cluster-randomized trial involving the Vi polysaccharide vaccine and an active control (Hepatitis A) was designed to determine the effectiveness and the feasibility of providing Vi vaccine under actual programmatic conditions in 2 contiguous urban wards in Kolkata. The vaccines used in this study are internationally produced and locally licensed. A 1 year pilot phase will precede the actual Vi-demonstration project. Surveillance for typhoid fever cases will continue after the mass immunization campaign. A passive surveillance system to evaluate adverse events following immunization will be implemented. Socio-economic studies will be conducted in parallel to the effectiveness evaluation. The knowledge, attitudes, beliefs and practices among parents and health care providers regarding typhoid illness, treatment and prevention will be assessed. Logistic, feasibility and vaccine costs will also be determined.


Sponsor: International Vaccine Institute

Current Primary Outcome: Total protection against S. typhi [ Time Frame: 2 years from zero time ]

Original Primary Outcome:

  • vaccine effectiveness
  • cost-effectiveness of Vi vaccination
  • adverse events
  • anti-Vi antibody response


Current Secondary Outcome:

  • Indirect protection against S. typhi [ Time Frame: 2 years from zero time ]
  • Overall protection against S. typhi [ Time Frame: 2 years from zero time ]
  • Total protection against S. paratyphi [ Time Frame: 2 years from zero time ]
  • Adverse event(s) following immunization [ Time Frame: 30 days from vaccination ]


Original Secondary Outcome:

  • logistic feasibility of typhoid mass immunization campaign
  • cost of treatment


Information By: International Vaccine Institute

Dates:
Date Received: July 28, 2005
Date Started: May 2003
Date Completion:
Last Updated: August 25, 2008
Last Verified: August 2008