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Effectiveness of a Typhoid Conjugate Vaccine in DRC

Phase 4
Recruiting
Conditions
Typhoid Fever
Interventions
Biological: Vi-TT
Registration Number
NCT05119426
Lead Sponsor
International Vaccine Institute
Brief Summary

This is a prospective cohort evaluation of vaccine effectiveness of a single dose of Typbar-TCV® against symptomatic blood culture-confirmed typhoid fever when administered through a mass vaccination campaign to children 9 months to \<16 years of age in Kisantu, DRC.

Detailed Description

This study is conducted in Kisantu, DRC and is comprised of a mass vaccination campaign of children aged 9 months to \<16 years with a single dose of Typbar-TCV® and a concomitant surveillance study to assess the incidence of culture-confirmed typhoid fever in the population during a period of three years following vaccination. Safety events will be monitored for 30 minutes following vaccination for all participants. In a subset of age-eligible participants living in the study area, the investigators will assess local and systemic solicited adverse events/adverse reactions and unsolicited adverse events occurring within the first 7 days post-vaccination and unsolicited and serious adverse events within 28 days post-vaccination. A population census will be conducted at baseline to enumerate and characterize the population under study and demographic information will be collected to allow for minimization of potential sources of bias during analysis. An interim censuses and a census at study closure will be carried out to update population information.

The investigators hypothesize that the Typbar-TCV® vaccine is effective in large scale vaccination campaigns, thereby lowering the incidence of blood-culture confirmed typhoid fever in children. Lessons and experiences on vaccination feasibility and uptake will be important for informing TCV introduction across the African continent.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
48000
Inclusion Criteria
  • Parent/guardian willing and able to provide informed consent; assent will be sought for participants between 12 and <16 years of age
  • Resident of the defined study area, Kisantu Health Zone at the time of vaccination
  • Age between 9 months and <16 years (i.e., ≤15 years and 364 days) on the day of vaccination
Exclusion Criteria
  • The participant has a known allergy to any of the vaccine components,
  • Any medical reason perceived to increase risk to health posed by vaccination as judged by a medical professional
  • Self-reported pregnancy in females greater or equal to 11 years of age who have reported menarche

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Vi-TTVi-TTSingle dose of Vi-TT to children 9 months to \<16 years of age
Primary Outcome Measures
NameTimeMethod
Direct vaccine effectiveness of Typbar-TCV®3 years

Comparison of incidence of blood culture confirmed Salmonella Typhi infection in participants 9 months to \<16 years of age vaccinated with a single dose of Typbar-TCV® delivered through a mass vaccination campaign and unvaccinated participants 9 months to \<16 years of ageSalmonella Typhi isolated from blood specimens using conventional microbiological techniques

Secondary Outcome Measures
NameTimeMethod
Safety profile of Typbar-TCV®28 days

Proportion of participants developing local and systemic solicited adverse events/adverse reactions and unsolicited adverse events within the first 7 days post-vaccination in a subset of vaccinees and unsolicited and serious adverse events within 28 days post-vaccination

Feasibility of a single-dose Typbar-TCV® mass campaign in Kisantu, DRC3 years

Descriptive report assessing both the scientific feasibility, including the ability of the study team to measure the above-named objectives, and operational feasibility, focusing on logistical aspects of the study conduct

Overall vaccine effectiveness of Typbar-TCV®3 years

Comparison of incidence of blood culture confirmed Salmonella Typhi infection in all individuals 9 months to \<16 years of age residing in clusters with lowest vaccine coverage (delineated virtually using GIS data) and all individuals 9 months to \<16 years of age residing in clusters with highest vaccine coverage

Total vaccine effectiveness of Typbar-TCV®3 years

Comparison of the incidence of blood culture confirmed Salmonella Typhi infection in vaccinated individuals 9 months to \<16 years of age residing in clusters with highest vaccine coverage (delineated virtually using GIS data) versus unvaccinated individuals 9 months to \<16 years of age residing in clusters with lowest vaccine coverage

Indirect vaccine effectiveness of Typbar-TCV®3 years

Comparison of the incidence of blood culture confirmed Salmonella Typhi infection in unvaccinated individuals 9 months to \<16 years residing in clusters with lowest levels of vaccine coverage (delineated virtually using GIS data) versus unvaccinated individuals 9 months to \<16 years of age residing in clusters with highest levels of vaccine coverage

Trial Locations

Locations (25)

CS Kavuaya

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

CS Kimuisi

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

CS Kintanu Etat

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Kisantu, Bas-Congo, Congo, The Democratic Republic of the

CS Yimbi

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

CS Lemfu

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Kisantu, Bas-Congo, Congo, The Democratic Republic of the

PS Kongo Nord

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

PS Ngombi Kinsambu

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Kisantu, Bas-Congo, Congo, The Democratic Republic of the

CS Kilenda

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

CS Kinkonko

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

CS Kipasa

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

CS Ngeba

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

Gare

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

CS Cederi Madimba

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Kisantu, Bas-Congo, Congo, The Democratic Republic of the

Nkandu 1

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

Site avancé de Kinsambamba

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

Cerphytoco

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

CS Kipako

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Kisantu, Bas-Congo, Congo, The Democratic Republic of the

CS Saint Pierre Boko

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Kisantu, Bas-Congo, Congo, The Democratic Republic of the

Kimayala

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Kisantu, Bas-Congo, Congo, The Democratic Republic of the

PS Kilemfu Nkanga

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Kisantu, Bas-Congo, Congo, The Democratic Republic of the

Unadic

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

Wete

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

Nkandu 2

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

CS Kivuangi

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

Nkandu 3

🇨🇩

Kisantu, Bas-Congo, Congo, The Democratic Republic of the

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