Study: Floods can increase health risks 3-6 weeks later

Oct. 6, 2023
A study published in the BMJ finds that risk of death can increase by 2.1% for up to 60 days after a flood event.

A new study finds that people impacted by a flooding event are at significantly increased risk of dying – including heart and lung problems – in a crucial window between three and six weeks after the event, even after the flooding has dissipated, according to a press release from Monash University.

The study, published in the BMJ, found that the risk of dying increased and persisted for up to 60 days (50 days for cardiovascular mortality) after a flooded day — increasing by for 2.1% for all-cause deaths, 2.6% for cardiovascular deaths, and 4.9% for respiratory deaths.

Flood events make up almost half (43%) of all natural disasters, and they are projected to increase in severity, duration, and frequency in the background of climate change. 23% of people are directly exposed to inundation depths of over 0.15 meters every decade.

The study provides the first timeline of the health impacts of flooding giving local health authorities and policy makers a blueprint as to when they should actively monitor flood-affected communities.

The study’s researchers studied 761 communities from 34 countries that had experienced at least one flood event during the decade from 2000-2019, reviewing a total of 47.6 million all-cause deaths including 11.1 million cardiovascular deaths, and 4.9 million respiratory deaths in the study time period.

The researchers studied daily counts of deaths during 2000-2019 in 761 communities from 34 countries that has experienced at least one flooding event during 2000-2019 and the proportions of deaths attributable to floods were calculated.

In the aftermath of a flood, deaths from natural causes may be triggered by contamination of food and water, exposure to pathogens (i.e., fungi, bacteria, and virus), impaired access to health services, and psychological impairment.

Photo 140625965 © Gibson Outdoor Photography |
Photo 153841418 © Kevin Ruck |
Photo 130624582 © Elen33 |
Photo 35168105 © Mary Martindale |