Assessment of Chikungunya Virus Seroprevalence Before VLA1553 Vaccination in the Municipalities Selected for Participation in the VLA1553 Pilot Vaccination Strategy in Brazil

Valneva

Status: Invitation-only

Conditions: Chikungunya Virus Infection

Treatments: Biological: Live-attenuated CHIKV vaccine VLA1553

Study type: Observational

Funder types: Other; Industry

Identifiers

NCT07163845

VLA1553-407

Details and patient eligibility

About

This is a cross-sectional serosurvey using household cluster sampling conducted before the VLA1553 pilot vaccination strategy will be implemented in about 10 municipalities in Brazil.

Full description

Households will be selected randomly using a multi-stage random sampling at the census tract, street, and household levels, to select study participants. The study aims to prospectively evaluate the association between vaccination uptake and previous CHIKV exposure (pre-existing immunity to CHIKV infection) in the age-group approved per label in Brazil (e.g., adults [≥18 years of age] or individuals ≥12 years of age). Seroprevalence among vaccinated and unvaccinated individuals will be used to parameterize a probabilistic bias analysis conducted as part of the VE study. Finally, the study will explore the prevalence of CHIKV exposure in the different study communities before the VLA1553 pilot vaccination strategy in individuals ≥2 years of age.

Enrollment: 4,988 estimated patients

Sex: All

Ages: 2+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

1. Individuals residing in the selected municipalities of Brazil where the VLA1553 pilot vaccination strategy will be implemented.
2. Individuals ≥2 years of age
3. Individuals who sleep 3 nights a week or more in a household that is selected by cluster sampling.

Exclusion criteria

1. Individuals or their legally accepted representatives (LAR) who are not willing or not able to provide informed consent (and assent, as required) according to country-specific procedures.