About This Project

Typhoid fever kills over 190,000 annually, with rising multi-drug-resistant (MDR) Salmonella strains worsening the crisis. Current vaccines lose effectiveness within 3–5 years, especially in children. We expect developing a multi-serotype phage-based vaccine using bacteriophage display technology will create lasting, adaptable immunity. We have already identified and expressed vaccine targets in phage-display mode. Our next step is to evaluate the effectiveness of this vaccine in mice

Ask the Scientists

What is the context of this research?

Typhoid fever is an illness caused by bacteria called Salmonella typhi. It affects millions yearly,mostly in places without reliable, clean water or good healthcare. The vaccines we have now don’t last long and don’t cover all types of Salmonella. That’s a big issue because other types, called non-typhoidal Salmonella, can also cause severe sickness.

I’m working on something new—a broad-coverage vaccine made with bacteriophages that can protect against multiple types of Salmonella. These are tiny viruses that naturally attack bacteria. Phage-based vaccines are cheap, safe and don’t need to be cold. That makes them perfect for rural areas where refrigeration and access to healthcare can be challenging.

Seeing how unfair vaccine access was during COVID-19 drove me to do this. Rich countries got vaccines first, while poorer ones had to wait. I want to help change that by creating an affordable, easy-to-distribute vaccine that works for typhoid.

What is the significance of this project?

This project focuses on developing a phage-based vaccine to combat Salmonella typhi, the cause of typhoid fever, and non-typhoidal Salmonella strains. Typhoid affects over 9 million people annually, with over 100,000 deaths, especially in low- and middle-income countries (LMICs). Existing vaccines offer limited protection, particularly against drug-resistant strains. Phage-based vaccines provide a cost-effective, stable, and ambient temperature-dependent alternative, ideal for regions with limited cold storage. The technology, developed at the University of Waterloo by Roderick , has demonstrated versatility, including in an intranasal COVID-19 vaccine. This project aims to create a broad-spectrum vaccine that can be locally produced in LMICs, addressing vaccine inequity and reducing dependence on external sources. By advancing this technology, we can improve global health preparedness and contribute to sustainable, accessible healthcare solutions for resource-limited regions.

What are the goals of the project?

In this project, I’m developing a phage-based vaccine targeting Salmonella typhi. I’ll use a phage to deliver components that trigger an immune response and then test the vaccine's immunogenicity in mice by measuring antibody production and T-cell activation. I will optimize the vaccine production process to ensure scalability for broader distribution.

I’ll test different vaccine administration routes—oral, intramuscular, and intranasal—to identify the most effective method. Additionally, I will assess vaccine stability under various environmental conditions to ensure it can be stored and transported without cold storage.

I’ll track long-term immunity by monitoring the presence of memory cells, ensuring lasting protection. lastly, the vaccine’s ability to provide cross-protection against non-typhoidal Salmonella strains will also be tested.