Assessment of the long-term efficacy of a dengue vaccine against symptomatic, virologically-confirmed dengue disease by baseline dengue serostatus
Vaccine·
- DOI
- 10.1016/j.vaccine.2020.03.029
- PMID
- 32204943
- PMCID
- —
- OpenAlex
- W3011273979
- Study type
- Journal article
- Publisher
- Elsevier BV
- Article type
- journal-article
- Integrity
- current
Why this research matters now
The findings provide evidence about longer-term vaccine performance across age and prior dengue-exposure groups. They may help frame evaluations of how serostatus and age relate to reported CYD-TDV efficacy.
Structured evidence summary
Research question
The study examined whether CYD-TDV efficacy against symptomatic, laboratory-confirmed dengue persisted during later follow-up and varied by baseline dengue serostatus and age.
Study design
This was a post-hoc analysis of the surveillance-extension period of two Phase III studies, covering approximately the fifth and sixth years after initial vaccination. Several methods were used to classify or estimate baseline serostatus.
Population and setting
Participants came from the CYD14 study in the Asia-Pacific region and CYD15 in Latin America. Analyses were stratified by dengue serostatus and age, including groups aged 2–5, 6–8, and at least 9 years.
Main findings
During extended follow-up, 436 symptomatic virologically confirmed dengue cases were reported. Among seropositive participants aged at least 9 years, estimated efficacy ranged from 47.9% to 53.0% across three analytic approaches; estimates were lower below age 9, while results among seronegative participants ranged from no apparent efficacy to modest efficacy.
Public-health relevance
The findings provide evidence about longer-term vaccine performance across age and prior dengue-exposure groups. They may help frame evaluations of how serostatus and age relate to reported CYD-TDV efficacy.
Important limitations
The analysis was post hoc, and baseline serostatus was evaluated using multiple approaches, including imputation and a later antibody-titer threshold. Interpretation is also limited to the supplied abstract and metadata; the full article is needed to assess methods, missing data, subgroup precision, and potential biases.
GIDS interpretation
The article is discoverable in a GIDS context under dengue, vaccination, vaccine effectiveness, and surveillance-related classifications. It supplies historical trial follow-up evidence and is not presented here as confirmation of any current surveillance signal.
Related GIDS surveillance
Literature context does not validate, explain, or change a surveillance signal. Exact and contextual relationships are shown separately.
Evidence relationships
This article has 11 auditable classifier relationships to diseases, places, topics, and study design.