iNOVVEL
The Invasive Non-Typhoidal Salmonella (iNTS) Vaccine Value Evaluation and Development (iNOVVEL) was established as a joint project by the International Vaccine Institute and WHO/Vaccine Product & Delivery Research Immunization, Vaccines and Biologicals in 2021 through funding support from the Wellcome Trust. From 2021–2025, it worked to develop a Full Value of Vaccine Assessment to ensure that safe, effective, and affordable iNTS vaccines were available and implemented to decrease the burden of iNTS disease in those most in need.
Age-standardized DALY rates (per 100,000) by location, both sexes combined, 2021

- Estimated to cause over 500,000 cases of invasive disease
- Leading to more than 79,000 deaths with a high case fatality ratio (14.5%)
- Affecting mostly infants and young children in low- and middle-income countries in sub-Saharan Africa
- Exhibits increasing levels of antibiotic resistance
While there are no iNTS vaccines available for use in humans, there are several potential candidate vaccines under development. These vaccine development pathways include a bivalent iNTS vaccine (Salmonella Typhimurium and Salmonella Enteritidis) and a trivalent vaccine (Salmonella typhi combined with iNTS).
Full Value of Vaccine Assessment for invasive Non-Typhoidal Salmonella Vaccines (2021–2025)
The objectives of iNOVVEL included the development of a vaccine research and development roadmap, Preferred Product Characteristics, the definition of the Regulatory Pathway, and provision of the rationale for investment in development and deployment of the vaccine through a Full Value of Vaccine Assessment.
Under the joint leadership through a consensus process, IVI and WHO worked together to develop WHO Preferred Product Characteristics for iNTS vaccines and R&D roadmap for iNTS vaccines following a series of consultation process (WHO Nontyphoidal Salmonella page, Report of a WHO expert consultation) as well as determining the Clinical Development Plan and Regulatory Pathway to bring iNTS vaccines to licensure and WHO prequalification.
Overview of timeline of development of Preferred Product Characteristics and research and development roadmap for iNTS vaccines

Full Value of Vaccine Assessment
IVI in collaboration with other partners (Shift Health, London School of Hygiene and Tropical Medicine, Swiss Tropical and Public Health Institute, and New York University) led the development of a Full Value of Vaccine Assessment to understand the value of investment in an iNTS vaccine and to develop a rationale for the development of a vaccine for iNTS from a multi-stakeholder perspective encompassing the business case, investment case, and broader societal benefits of vaccines.
Meeting reports and publications
- WHO Expert Consultation on Non-Typhoidal Salmonella and Broadly Protective Salmonella Vaccines, Geneva, 22-24 Sep 2021
- WHO Expert Consultation on Invasive Non-Typhoidal Salmonella (iNTS) Landscape Analysis and LMIC Stakeholder Consultation on Invasive Non-Typhoidal Salmonella (iNTS) Vaccine Use Case and Demand, Geneva, 29 Nov – 1st Dec 2021
- IVI-WHO consultation on Salmonella combination vaccines, Kigali (Dec 3,2023)
- IVI-WHO-Wellcome Trust consultation on iNTS combination vaccines, Geneva (Dec 12-13, 2024)
- IVI-WHO consultation on regulatory considerations to support licensure of iNTS vaccines for use in children in LMIC, Nairobi (Feb 4-5, 2025)
- IVIR-AC meeting on iNTS FVVA (virtual), Feb 18, 2025
Immunization and vaccines related implementation research advisory committee (IVIR-AC) – February 2025 - The Economic Burden of Non-Typhoidal Salmonella and Invasive Non-Typhoidal Salmonella Infection: A Systematic Literature Review
- A systematised review and evidence synthesis on the broader societal impact of vaccines against Salmonella
- Landscape analysis of invasive non-typhoidal salmonella (iNTS) disease and iNTS vaccine use case and demand: Report of a WHO expert consultation
- Non-typhoidal Salmonella combination vaccines: clinical development plan and regulatory considerations
- The invasive non-typhoidal Salmonella vaccine landscape: Innovations and challenges ahead
- Need, demand, and feasibility for a new iNTS vaccine: stakeholder insights from eight African countries
- Country-level perspectives and priorities to guide the development of Invasive non-Typhoidal Salmonella (iNTS) vaccines: Insights from seven countries

