Impact Study of Cholera Vaccination in Endemic Areas - Clinical Surveillance

Cholera Control in Endemic Regions of Africa: Clinical Surveillance and Cholera Shedding Study in the Context of Mass Vaccination Campaigns, Democratic Republic of the Congo

This project aims to fill this essential knowledge gap by assessing the impact of oral cholera vaccine mass campaigns in 2 sites (urban and rural) in DRC, described in this protocol. The evidence generated from this project will be key to develop future strategies regarding cholera vaccine use in endemic settings, including places with higher burden in terms of cholera mortality.

Study Overview

• Status: Recruiting
• Conditions: Cholera

Detailed Description

The project will comprise three different components:

1. Clinical cholera surveillance to measure cholera diseases incidence in selected African hotspots targeted by vaccination.
2. Serial serological surveys to measure the prevalence of recent cholera infection (within the last 12 months).
3. Identification and follow up of individuals with positive V. cholerae shedding (symptomatic or asymptomatic) among sero-survey participants and among household members of cholera confirmed cases.

The present protocol relates to the setup of clinical surveillance and the follow up of individuals with positive V. cholerae shedding identified through clinical surveillance, in DRC.

This protocol will allow us to assess if a large vaccination campaign reaching high coverage in cholera hotspot in Africa can allow sustained control of cholera for at least two years, by fulfilling the following specific objectives:

• To measure cholera incidence rates following the mass vaccination campaign in two cholera hotspots in Africa.
• To assess the duration of shedding among vaccinated and unvaccinated individuals and the duration of viable V. cholerae in the peri-household environment.
• To measure the secondary cholera attack rates (symptomatic and asymptomatic) at household level among vaccinated and unvaccinated individuals following the identification of an index case in a given household.
• To describe the global genetic diversity of V. cholerae strains in the study areas and within households affected by cholera.
• To develop sustainable surveillance methods that could be applied in other hotspots in Africa and elsewhere aiming to monitor the impact of the cholera control program.

• Study Type: Observational
• Enrollment (Estimated): 6000

Contacts and Locations

• Study Contact: Name: Anais BROBAN; Phone Number: +33140215494; Email: anais.broban@epicentre.msf.org
• Study Contact Backup: Name: Flavio Finger; Email: flavio.finger@epicentre.msf.org

Study Locations

• Congo, The Democratic Republic of the
  • Goma, Congo, The Democratic Republic of the
    • Recruiting
    • Anais Broban
    • Contact: Anais BROBAN; Phone Number: 0140215429; Email: anais.broban@epicentre.msf.org

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

All patients presenting to a CTC/UTC with a watery diarrhoea (≥ 3 watery stools per day), with or without vomiting, with or without dehydration.

For the follow-up of individuals with active cholera shedding:

This activity will take place in the community at included patient's households. Patients will be identified through CTC/CTUs and will therefore be conducted in the catchment area of these structures.

Description

For Surveillance in study CTCs

Inclusion Criteria:

• All patients presenting at the time of the study to any selected Cholera Treatment Center/Cholera Treatment Unit (CTC/CTU), matching the case definition and giving his/her consent (or assent for children 8 to 17 years old) to participate in the study will be eligible.

Exclusion Criteria:

• Patients who decline to participate will be excluded from the study.

Follow up of individuals with active cholera shedding:

Inclusion Criteria:

1. present to any selected CTC/CTU, match the case definition, participate to the clinical surveillance activity and test positive to RDT OR
2. Be a household member of a person respecting inclusion criteria 1. AND for whom the head of the household has provided verbal consent to participate AND giving his/her consent (or assent for children 8 to 17 years old) to participate in the study will be eligible.

Exclusion Criteria:

- Individuals who decline to participate will be excluded from the study, as well as households for whom the head of the household (and his or her representative) decline the participation of his/her household.

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To better characterize cholera transmission in cholera hotspot in Africa and assess the impact of a large vaccination campaign reaching high coverage on sustained control of cholera transmission for at least two years.	Specific objectives 1 and 4 will be answered through the clinical surveillance activity, below referred to as "Surveillance in study CTCs", while 2 and 3 relate to the follow-up activity, below referred to as "Follow-up of individuals with active cholera shedding".	2 years

Secondary Outcome Measures

Outcome Measure	Time Frame
1. To retrospectively study surveillance data, and prospectively measure cholera incidence rates of medically-attended confirmed cases following the mass vaccination campaign in two cholera hotspots in Africa.	2 years
2. To assess the duration of shedding among vaccinated and unvaccinated individuals and the duration of viable V. cholerae in the peri-household environment.	one year
3. To measure the secondary cholera attack rates (symptomatic and asymptomatic) at household level among vaccinated and unvaccinated individuals following the identification of an index case in a given household.	one year
4. To describe the global genetic diversity of V. cholerae strains in the study areas and within households affected by cholera.	2 years

Collaborators and Investigators

• Sponsor: Epicentre
• Collaborators: Wellcome Trust; Ministry of Public Health, Democratic Republic of the Congo; Médecins Sans Frontières, France; Institut National de Recherche Biomédicale. Goma, République Démocratique du Congo; Grand Labo de Lubumbashi
• Investigators: Study Director: Klaudia PORTEN, Epicentre; Study Chair: Francesco Luquero, GAVI

Study record dates

Study Major Dates

• Study Start (Actual): May 11, 2021
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: April 16, 2021
• First Submitted That Met QC Criteria: April 16, 2021
• First Posted (Actual): April 21, 2021

Study Record Updates

• Last Update Posted (Actual): September 19, 2024
• Last Update Submitted That Met QC Criteria: September 11, 2024
• Last Verified: September 1, 2024

More Information

Terms related to this study

• Keywords: Mass vaccination campaign; Cholera incidence rates; V.Cholerae
• Additional Relevant MeSH Terms: Infections; Gram-Negative Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Vibrio Infections; Cholera
• Other Study ID Numbers: 2104-WT; 215689/Z/19/Z (Other Grant/Funding Number: Wellcome Trust)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: Datasets gathered during this study are susceptible to be made available to other research groups which are currently actively collaborating with Epicentre in the cholera research projects. In that case, data sharing agreements will be made with the relevant research groups.
• IPD Sharing Access Criteria: Partners of the study / Data Sharing Agreement and/or Memorandum of Understanding signed
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No