Typhoid Conjugate Vaccine Introduction in Navi Mumbai, India

Brief Title

Typhoid Conjugate Vaccine Introduction in Navi Mumbai, India

Official Title

Evaluation of a Typhoid Conjugate Vaccine Introduction Program in Navi Mumbai, India

Brief Summary

      The purpose of this study is to evaluate the impact of a government-led typhoid conjugate
      vaccine introduction program on typhoid disease burden in Navi Mumbai, India.
    

Detailed Description

      A new generation of typhoid conjugate vaccines (TCVs) have been shown to be safe and provide
      long-lasting immunity in children. In India, Typbar TCV Vi-TT (Vi capsular polysaccharide
      conjugated with tetanus toxoid protein) is manufactured by Bharat Biotech International
      Limited (BBIL). Immunogenicity studies by BBIL showed >90% detectable antibodies to Typbar
      TCV vaccine at 42 days and >70% at 720 days in persons 2-45 years old. A single dose of
      vaccine was effective in children 6-23 months old with 98% seroconversion at 42 days and
      persistent high antibody titers at 720 days. Another randomized controlled trial study by
      University of Oxford tested Vi-TT with a human challenge model of typhoid fever in which
      participants ingested Salmonella Typhi after vaccination. Typhoid fever was diagnosed by
      clinical criteria and/or positive blood culture at 2 weeks in 77% of controls (n=31) as
      compared to 35% in the Vi-TT group (n=37) to give vaccine efficacy of 54% (95% confidence
      interval of 26-71). Typbar TCV has been licensed in India for children >6 months old since
      2013 and is currently used in the private sector. In January 2018, the World Health
      Organization (WHO) recommended the use of typhoid conjugate vaccines especially in those
      countries with the highest burden of disease and the highest burden of antimicrobial
      resistance. However, there are no field effectiveness studies yet for Typbar TCV.

      In this study, a hybrid facility- and community-based typhoid surveillance strategy will be
      used to evaluate the impact of a government-led typhoid conjugate vaccine introduction
      program on typhoid disease burden in Navi Mumbai, India. Navi Mumbai is a metropolitan area
      extending from Mumbai with approximately 1.4 million people and wide demographic and
      socioeconomic strata, including slums. Navi Mumbai is comprised of 13 area nodes, and 8 of
      these nodes are under the jurisdiction of the local government body, Navi Mumbai Municipal
      Corporation (NMMC). Navi Mumbai has high enteric fever burden: a 2008 study found 98 blood
      culture-confirmed pediatric cases over 16 months in 2 hospitals with a majority of isolates
      exhibiting multi-drug resistance. Data from one private laboratory in 2015 showed over 225 S.
      Typhi cases including 3 cases with ceftriaxone resistance.

      NMMC has decided to introduce TCV into public sector routine immunization services and will
      vaccinate all children 9 months to <15 years old within its jurisdiction - estimated 390,000
      children - with TCV over 2 years. NMMC government officials are collaborating with
      researchers from WHO India, Institute of Cholera and Enteric Diseases (NICED), Centers for
      Disease Control and Prevention (CDC), and Stanford University to implement the TCV
      introduction in a two-phase cluster-randomized program in order to allow rigorous evaluation
      of population impact. NMMC has 22 urban health posts (UHPs) that give routine childhood
      immunizations. UHPs were first grouped into 3 strata based on % of population living in
      slums: low, medium, or high. Half of the UHPs within each stratum were then randomly selected
      to receive TCV in 2018 (Phase 1) and the remaining UHPs to receive TCV one year later in 2019
      (Phase 2).

      Evaluation studies of NMMC's TCV introduction program include: impact on blood-culture
      confirmed typhoid fever; impact on clinical syndromes of febrile illness; vaccine safety;
      vaccine efficacy; vaccination campaign coverage and acceptability surveys; environmental
      water contamination with Salmonella Typhi; seroconversion associated with typhoid infection;
      and cost-effectiveness of typhoid conjugate vaccination campaign.
    

Study Type

Observational

Primary Outcome

blood culture-confirmed typhoid fever

Secondary Outcome

 Adverse events following immunization

Condition

Enteric Fever

Intervention

Typhoid Conjugate Vaccine

Study Arms / Comparison Groups

 Phase 1: TCV in 2018

Description:  Children receiving TCV (typhoid conjugate vaccine) in 2018 vaccination campaign by NMMC.

Publications

* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.

Recruitment Status

Biological

Estimated Enrollment

17292

Start Date

July 2, 2018

Completion Date

March 31, 2021

Primary Completion Date

March 31, 2021

Eligibility Criteria

        Inclusion Criteria:

        For overall study,

          1. For hospital-based surveillance, children age 6 months to 16 years.

          2. For community-based surveys, adult members of households with children <16 years old.

          3. Parental consent (and child assent for >12 years) given.

        For hospital-based surveillance for typhoid fever, additional criteria include: history of
        fever for >72 hours within the last 7 days without upper respiratory tract symptoms and
        vesicular rash; strong clinical suspicion of enteric fever including ileal perforations; or
        diagnosis of enteric fever confirmed by positive blood cultures or histopathology. For
        outpatients, additional criterion of living in areas governed by Navi Mumbai Municipal
        Corporation.

        For hospital-based surveillance of adverse events of special interest, timing will focus on
        one month prior to and 42 days after the vaccination campaign. Diagnoses included are:
        anaphylaxis, bronchospasm, urticaria, Guillain-Barré syndrome, meningitis, encephalitis,
        myelitis, seizures, thrombocytopenia, and sudden death.

        For all community surveys, additional criterion of living in areas governed by Navi Mumbai
        Municipal Corporation.

        Exclusion Criteria:

        For all study components,

          1. Already enrolled in same study component.

          2. No informed consent or assent given.

        For hospital-based surveillance for typhoid fever, additional exclusion criteria are: fever
        <72 hours, symptoms of upper respiratory tract infection (coryza, rhinorrhea), and
        vesicular exanthem. For outpatients, those living outside of NMMC-governed areas will be
        excluded.

        For community surveys, households without children <16 years old and households in which
        there is no adult (>18 years old) at time of survey will be excluded.
      

Gender

All

Ages

6 Months - 16 Years

Accepts Healthy Volunteers

Accepts Healthy Volunteers

Contacts

Stephen Luby, MD, , 

Location Countries

India

Location Countries

India

NCT ID

NCT03554213

Organization ID

IRB-39627

Secondary IDs

OPP1169264

Responsible Party

Principal Investigator

Study Sponsor

Stanford University

Collaborators

 Centers for Disease Control and Prevention

Study Sponsor

Stephen Luby, MD, Principal Investigator, Stanford University

Verification Date

September 2021