Risks to Health in Flooding Situations: Illnesses, Wounds, and Psychological Distress
Floodwater isn't merely rain. It's often contaminated with sewage, bacteria, and chemicals. Hidden sharp objects made of metal or glass can also lurk in its murky depths.
According to environmentalist Wilma Subra, exposure to this contaminated water can irritate the skin, causing boils or rashes, especially on parts of the body that have been submerged for an extended period. While brief skin contact isn't a significant issue, even a minor cut or scrape can serve as an entry point for harmful bacteria and viruses.
Chemicals in floodwater can also lead to skin irritation and burns after exposure.
Diseases from floodwater
Floodwater can carry diseases. This is a persistent problem in developing countries where diseases like cholera, typhoid, or yellow fever are prevalent, as mentioned by the World Health Organization. However, these diseases are uncommon in the United States, so a widespread outbreak is unlikely.
What is more common in the US are cases of diarrhea and other stomach problems after contact with contaminated floodwater or consumption of contaminated food or drink. Floodwater can contaminate drinking water, particularly from private wells, as stated by the US Centers for Disease Control and Prevention. These wells should be tested before use if they come into contact with floodwater.
For municipal water, state and local health departments will provide guidance on whether it needs to be boiled or treated before use.
Using items that have been submerged in floodwater can also cause stomach problems. To prevent illness in children, the CDC strongly advises parents not to let their kids play with toys that have been in the water unless they've been disinfected with a bleach solution.
Exposure to floodwater can increase a person's risk of ear, nose, and throat problems, as several studies have shown, but most of these issues involve individual cases and do not result in epidemics.
The occasional stomach bug or respiratory infection is more likely among people who have to live in close quarters with large groups. Under flood conditions, maintaining high hygiene standards is challenging, and the spread of germs is easier in shelters with large groups.
The CDC advises that people staying in shelters be extra vigilant and regularly wash their hands or use alcohol-based hand sanitizer to prevent the spread of disease.
Health-related cleanup challenges
Doctors often see an increase in respiratory infections after floodwaters recede and people are allowed to return to their homes. Contamination from floodwaters and the mold that rapidly grows in warm environments like Florida or Georgia can exacerbate asthma or trigger allergies.
The CDC recommends wearing rubber boots and gloves when cleaning homes and avoiding direct contact with items that have been in floodwater. Experts also suggest wearing a mask or respirator.
If floodwater has entered a home, it should be dried out as soon as possible to prevent mold. If it has stopped raining, windows and doors should be opened to speed up the drying process. Dehumidifiers should be used if there is power, and fans should be placed at doors and windows to blow air out, not inward, to prevent the spread of mold.
Walls, floors, and any hard surface that has come into contact with floodwater – such as appliances, countertops, and children's play areas – needs to be cleaned with soap and water and disinfected with a bleach solution. If walls or floors need to be replaced or refinished, everything needs to be thoroughly cleaned and dried to prevent mold growth, as per the Environmental Protection Agency.
Fabrics should be washed in hot water or dry-cleaned. Furniture that can be saved should be dried in the sun and then sprayed with disinfectant. Carpets should be steam-cleaned.
Food and beverages that have come into contact with floodwater should be thrown away. The US Food and Drug Administration suggests that people also discard prescription drugs – even those in their original containers or with screw tops – as they may no longer be safe if they've come into contact with contaminated water.
Risks from standing water: animals and electrocution
Floods typically drive out mosquitoes and disrupt their breeding cycle, but when the water recedes, there is an increased risk of infection with a mosquito-borne illness like West Nile or, as one 2019 study showed, Zika.
Mosquitoes that carry disease thrive in standing water and breed quickly when there is a lot of it. After Hurricane Katrina, for example, areas directly affected saw a significant increase in cases of West Nile.
The CDC recommends that people who are working or living near standing water take extra precautions to use bug spray with DEET or picaridin. Wear long sleeves, pants, and socks outdoors, even if it is warm, to prevent mosquito bites.
Mosquitoes aren't the only insect – or even the only animal – to worry about after a storm. When snakes are displaced by a flood, they often seek shelter and food closer to people than they usually would. Flood-damaged structures can be a magnet for snakes because it's easier for them to get in and hide under debris.
Wildlife specialists recommend wearing snake-proof boots at least 10 inches high, and people cleaning up debris should grab it from the top if possible rather than placing fingers beneath.
Other critters that might get displaced by floods comprise ants, mice, spiders, reptiles, alligators, and even family pets. The CDC suggests maintaining a safe distance to avoid getting bitten.
Water that's continually surging can also become electrically charged due to power lines that have fallen underwater or those that are underground but still functional. This leaves you exposed to the risk of electrocution.
Psychological concerns
However, aside from the physical hazards of floodwater, the most critical health issue, according to studies, is psychological.
Hurricanes and floods frequently trigger anxiety, depression, and stress. Storms can worsen existing mental health issues or even spawn new ones.
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Mental distress and stress are typical during and post-disaster. Emotions might run high, sleep could be disrupted, a desire for solitude could intensify, thoughts may lose clarity, and it may become difficult to recall things or focus on conversations. It can also be challenging to accept help, psychologists suggest.
Some individuals might develop complications related to the ongoing challenges associated with post-traumatic stress disorder, but the majority of those affected should overcome these issues with time.
People's resilience is remarkable, and most of us can adjust after a disaster, psychologists say. Those who have strong connections with family, friends, and colleagues generally recover faster, so psychologists recommend nurturing these bonds to speed up the recovery process.
For people facing lasting psychological challenges, counseling is strongly recommended. The federal government provides a Disaster Distress Helpline to assist those struggling with mental health issues resulting from a storm. The toll-free number, manned by mental health professionals, is 1-800-985-5990.
Research has shown that suicide may also be a risk following a natural disaster. The 988 Suicide and Crisis Lifeline provides free, emotional support to individuals during mental health crises and connects them to local resources. The service operates 24/7, 7 days a week, and has over 200 local crisis centers nationwide.
The chemicals in floodwater can cause skin irritation and burns after exposure, adding to health concerns. According to the Centers for Disease Control and Prevention, diseases like diarrhea and other stomach problems are common after contact with contaminated floodwater or consumption of contaminated food or drink.
