Salmonella Typhi and Salmonella Paratyphi A are the causative aetiologies typhoid and paratyphoid fever, which are collectively referred to as enteric fever. S. Paratyphi A disease is endemic in South and South East Asia. In 2021 it was estimated to cause >2 million illnesses and >14,000 deaths. There are currently three WHO-prequalified conjugate vaccines against S. Typhi, known as TCVs, but none to date to protect against S. Paratyphi A. There are currently several bivalent S. Typhi/Paratyphi A vaccine candidates in development.
WHO is seeking feedback on preferred product characteristics (PPCs) and the research and development technology roadmap for the development and licensure of bivalent Salmonella Typhi/Paratyphi A vaccines. These documents were developments through a series of consultations with the technical advisory group on Salmonella vaccines, and with advise of ad-hoc external experts. Vaccine PPCs and R&D technology roadmaps are published by the WHO Department of Immunization, Vaccines and Biologicals, and aim to provide stakeholders with strategic guidance on preferences for new vaccines, specifically from a LMIC perspective. Roadmaps aim to provide a framework outlining priority activities for global stakeholders to accelerate availability of effective vaccines, particularly in LMICs.
Please provide comments on these documents using the document provided on the link below.
Please feel free to contact vaccines@who.int for further information. Comments may be submitted by individuals or organizations, and will be accepted until 20 September 2024. Inputs received from this public consultation will contribute to the finalization of these documents.