Salmonella Combination Vaccines: Moving Beyond Typhoid

Area of Science:

• Immunology and Vaccinology
• Infectious Diseases
• Public Health

Background:

• Existing typhoid conjugate vaccines are increasingly available, but typhoid fever accounts for less than half of the global Salmonella disease burden.
• Invasive nontyphoidal Salmonella disease is prevalent in Africa, and paratyphoid A contributes significantly to enteric fever in Asia.
• Current vaccine strategies do not fully address the diverse spectrum of Salmonella-related illnesses worldwide.

Purpose of the Study:

• To advocate for the development and use of combination Salmonella vaccines.
• To review the existing pipeline of combination Salmonella vaccines.
• To discuss critical factors for developing and implementing these vaccines globally.

Main Methods:

• Literature review and analysis of the current Salmonella vaccine landscape.
• Exploration of epidemiological data on Salmonella disease burden globally.
• Discussion of strategic considerations for vaccine development, including target geographies, age groups, and regulatory pathways.

Main Results:

• A trivalent vaccine targeting typhoid and nontyphoidal Salmonella is suitable for Africa.
• A bivalent vaccine for enteric fever is relevant for Asia.
• A quadrivalent vaccine covering the four main disease-causing Salmonella enterica serovars offers a potential single solution for global Salmonella coverage.

Conclusions:

• Combination Salmonella vaccines are essential to address the full spectrum of Salmonella diseases.
• Geographically tailored vaccines (trivalent for Africa, bivalent for Asia) are valuable.
• A quadrivalent vaccine presents a unified approach for global Salmonella disease prevention.