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Last update: 2022-03-21

Key facts

  • Flooding is a common disaster. Acute and/or severe flooding can cause loss of life, significant infrastructure damage and displacement of the affected population.
  • Floods are often characterized by difficulty in accessing certain geographical areas. Depending on the severity, it can take days or weeks for floodwater to recede.
  • Flooding is exacerbated by climate change.
  • Floods often damage the health facilities and their services, impacting access to essential care such as maternal and child health care.
  • Drowning and trauma (injury) are most likely during a flood or in the immediate aftermath. In the days, weeks (and sometimes months) following a flood, the main health concerns include diarrhoeal diseases, vector-borne diseases, respiratory and skin infections and other adverse health outcomes.

Main health impacts

Health concern Risk factors
Diarrhoeal diseases Contamination of water supplies by flood water, damaged or destroyed sanitation facilities, crowded areas and poor hygiene practices.
Vector-borne diseases

Floods can result in an increase in breeding sites for mosquitoes in stagnant water, and after some time an increase in transmission of dengue, chikungunya and/or malaria.

Other vectors such as rats can be affected and their number increased because of poor hygiene conditions, bringing them in closer contact with humans, and leading to an increase in incidence of Leptospirosis.

Respiratory illnesses, skin disease and vaccine-preventable diseases Significant population displacement and overcrowded, communal emergency shelters coupled with poor hygiene can lead to respiratory illnesses or skin diseases. Flood water does not increase the risk of tetanus, but emergency responders and community members may be at increased risk for wounds and injuries that become contaminated with flood waters, soil, dirt, human or animal waste. It is important that Red Cross Red Crescent responders are up to date with tetanus vaccination.
Malnutrition Flooding can lead to a loss of food stock and crops, which can increase the risk of malnutrition.

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