Effectiveness of the TYPHIBEV® (Vi-CRM197 conjugate) vaccine introduction in Nepal: A test-negative, case-control study
Journal of Infection·
- DOI
- 10.1016/j.jinf.2026.106719
- PMID
- 41806875
- PMCID
- —
- OpenAlex
- W7134173653
- Study type
- Case-control study
- Publisher
- Elsevier BV
- Article type
- journal-article
- Integrity
- current
Why this research matters now
The documented high protection rate suggests utility for national immunization programs aiming to reduce severe bacterial enteric disease in endemic regions.
Structured evidence summary
Research question
The study investigates whether the TYPHIBEV® conjugate vaccine reduces the risk of laboratory-confirmed typhoid fever in pediatric populations following its national deployment.
Study design
Researchers utilized a test-negative, matched case-control methodology comparing children with positive blood cultures for Salmonella Typhi against those with negative results.
Population and setting
The analysis focused on vaccine-eligible children seeking care at designated health facilities throughout Nepal between October 2022 and December 2024.
Main findings
Overall vaccine effectiveness reached eighty-nine percent against confirmed infections. The protective effect appeared diminished in certain pediatric age brackets, although precise subgroup metrics were truncated in the provided text.
Public-health relevance
The documented high protection rate suggests utility for national immunization programs aiming to reduce severe bacterial enteric disease in endemic regions.
Important limitations
The investigation relies exclusively on blood culture confirmation, which may miss non-bacteremic presentations. Additionally, the abstract truncates key details regarding reduced efficacy in specific age groups.
GIDS interpretation
This record supplies peer-reviewed epidemiological context concerning a specific typhoid immunization strategy in South Asia, serving as historical reference material rather than an indicator of current transmission dynamics.
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 13 auditable classifier relationships to diseases, places, topics, and study design.