By InvitationNot Applicable

Observational Study to Assess the Effectiveness of VLA1553 Vaccine in Preventing Chikungunya During a Pilot Vaccination Strategy in Brazil

Brazil1,200 participantsStarted 2026-02-02

Plain-language summary

This is an observational, non-interventional, test-negative case-control (TNCC) study to estimate the vaccine effectiveness of VLA1553 against Chikungunya virus in a real-world setting.

Who can participate

Age range18 Years – 59 Years

SexALL

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Inclusion criteria

✓. Have place of residence in a municipality where the pilot vaccination strategy is implemented;
✓. Are in an eligible age-group to receive the VLA1553 vaccine;
✓. Have been notified in SINAN as a suspected case for CHIK or Dengue surveillance during the study period;
✓. Have a sample registered in GAL that is collected within 0-5 days following the onset of CHIKV-like symptoms and is tested for CHIKV using RT-PCR;
✓. Have complete data in the Brazilian MoH databases (SINAN and GAL) on age, sex, municipality of residence, sample collection date, and date of symptom onset and the healthcare facilities where the suspected case was reported.

Exclusion criteria

✕. Have inconclusive RT-PCR result for CHIKV;
✕. Have the first CHIKV-like symptom onset less than 14 days from date of vaccination.

What they're measuring

Detection of CHIKV in VLA1553-vaccinated (≥14 days after vaccination) and unvaccinated study individuals with CHIKV-like symptoms confirmed by reverse transcriptase polymerase chain reaction (RT-PCR).

Timeframe: Study start through study completion, an average of 23 months

Trial details

NCT IDNCT07347002

SponsorValneva Austria GmbH

Sponsor typeINDUSTRY

Study typeOBSERVATIONAL

Primary completion2027-12-31

View on ClinicalTrials.gov More Chikungunya Virus Infection trials