Typhoid fever

Typhoid fever is caused by infection with the bacterial species Salmonella typhi. It is transmitted through contaminated food and water. These often materialize due to poor sanitation, lack of clean drinking water, and urbanization combined with overcrowded populations. These issues are exacerbated by climate change and bacterial strains evolving antimicrobial resistance.^[1]

One-third of the global typhoid burden is borne by India. A modelling study estimated 4.9 million cases and 7850 deaths in 2023 in India,^[2] underscoring the need to estimate disease burden and understand environmental factors driving disease transmission.

How we address this challenge

• Develop age-stratified compartmental models for typhoid including environmental variables and seasonal forcing.
• Develop agent-based models for urban locations incorporating hydrology.

Ongoing work

We developed a compartmental modelling framework and conducted representative simulations to benchmark model performance. By incorporating environmental and hydrological factors, this modelling framework provides a robust foundation for understanding how typhoid spreads and identifying effective intervention points.

References

1. Maskalyk, J. (2003). Typhoid fever. CMAJ, 169(2), 132.
   https://pmc.ncbi.nlm.nih.gov/articles/PMC164981/
2. Mogasale, V. V., John, J., Sahai, N., Ray, A., Farooqui, H. H., Mogasale, V., Dhoubhadel, B. G., Edmunds, W. J., Clark, A., & Abbas, K. (2026). Burden of typhoid fever and antimicrobial resistance in India (2023): A modelling study. The Lancet Regional Health-Southeast Asia, 44, 100714.
   https://doi.org/10.1016/j.lansea.2025.100714