In early 2018, drought-stricken Cape Town narrowly averted its “Day Zero,” the day when taps in the city would have run dry. Reservoirs filled up just enough to avert an all-out water crisis, and “Day Zero” has now been pushed to 2019. Meanwhile, in 2016, 2017, and 2018, floods in South Asia, Africa, Europe, and the United States have led to urban interruptions, evacuations, and deadly landslides.
Climate change experts have predicted that global water shortages and floods may be a harbinger of things to come. Recently there have been drought crises in California, Brazil, and Spain and changing weather patterns are increasing the number of extreme weather events, including heavy storms and rising sea levels, leading to floods that severely affect those living by rivers and seas.
For those of us who have access to readily available water and strong urban infrastructure, scenarios such as “Day Zero” and waist-deep floods seem like a distant reality. But, many communities living in developing countries are in a much more vulnerable position: These events can be devastating and have a huge impact on human health.
When Climate and Water Fluctuate: The Case of Cholera
Drought and floods have some obvious consequences. Drought stresses natural, agricultural, and livestock resources and creates conflict among water users. Floods can result in loss of human life as well as crops and livestock, property damage, and non-functioning infrastructure facilities. From these impacts, it is easy to see how drought and floods affect public health: Limited availability of clean water and food jeopardizes healthy individuals and communities. However, alarmingly, droughts and floods not only limit access to necessities, but also affect public health by accelerating the transmission of water borne diseases such as cholera.
A highly infectious and ancient disease spread by water and food, cholera had mostly disappeared from developed countries during the last 50 years. However, in recent years cholera cases have been increasing at an alarming rate, and outbreaks are re-emerging in many countries. Evidence suggests that climate is playing an increasing role in the resurgence of this infectious disease, and analysis of historical weather and epidemiological data over a 70-year period draws a clear link between climate change and the rise of cholera cases. Rising sea water temps, water scarcity caused by droughts, and damage to infrastructure from frequent and extreme weather-related events hinder people’s access to safe water and sanitation and the ability to practice good hygiene, all of which are key to preventing the spread of cholera.