Date of Award

January 2023

Document Type

Open Access Thesis

Degree Name

Master of Public Health (MPH)


School of Public Health

First Advisor

Albert Ko


Precipitation events such as hurricanes, typhoons, and heavy rainfall can have devastating impacts on water and sanitation infrastructure around the world and have led to large-scale waterborne outbreaks. As climate change amplifies the frequency and intensity of extreme weather events, it is also triggering an increase in waterborne disease transmission. This master’s thesis consists of a systematic review of academic literature pertaining to extreme precipitation events and the pathways by which they trigger waterborne outbreaks.

A systematic review of the literature in PubMed was conducted to identify waterborne disease outbreaks associated with extreme precipitation. The initial search yielded 3,248 results for title and abstract screening, of which 173 full-text articles were subsequently retrieved and screened on inclusion criteria of extreme precipitation, waterborne disease outcomes, and importantly, discussion of mediators and mechanisms driving the association. Ultimately, 57 studies were included in the review, representing study locations in 73 countries. The waterborne diseases studied were primarily gastrointestinal illnesses and were caused by bacteria, viruses, and parasites. The most common pathogens studied included bacteria of the genera Leptospira (23%) and Shigella (11%), as well as parasites of the genus Cryptosporidium (11%). Heavy rainfall (33%) and flooding (32%) were the most common events associated with waterborne disease outbreaks.

Ultimately, the most common mediators of waterborne transmission following an extreme precipitation event were (1) hydro-ecological risk factors, related to runoff from industrial, agricultural, or environmental sources (2) infrastructural risk factors, resulting from damage to or disruption of WASH (Water, Sanitation, and Hygiene) infrastructure, (3) socio-behavioral risk factors, arising from existing vulnerabilities or from changes in activities and behaviours, and (4) physical risk factors, due to contact with contaminated storm water or floodwaters. By examining and understanding these climate-related drivers of waterborne disease transmission, we can begin to envision better mitigation and prevention strategies to protect public health around the globe.


This is an Open Access Thesis.

Open Access

This Article is Open Access