Why is flood water dangerous? - Health Channel


Why is flood water dangerous? |

Why is flood water dangerous?
“Water, water, everywhere,
And all the boards did shrink;
Water, water, everywhere,
Nor any drop to drink.”

― Samuel Taylor Coleridge, The Rime of the Ancient Mariner

Hurricanes Harvey and Irma have recently flooded Texas, Florida and surrounding states, causing an estimated $200 billion in damage (similar to the costs of Katrina in 2005). Images of people wading, swimming and boating through city streets are all over the news. But flood waters are not just damaging to property, they are a potential health hazard as well.

Flood water mixes with everything it covers, including sewage, animal waste, pesticides, and a host of chemicals normally carefully contained. Bacterial counts in flood water are often extremely high, and this poses a risk for skin infections and digestive issues if the water is swallowed. Mosquitoes thrive in stagnant water, and the viruses that they carry (such as West Nile or Zika) can blossom after a flood. Wet carpets, floors, and wood promote mold growth which can lead to respiratory problems for those living in homes damaged by flood waters.

If you are living in a flooded region, there are some things you can do to protect your health:

  1. Stay out of moving water. Did you know that just 6 inches of moving water can cause you to lose your footing, and two feet of it can carry you (or your car) away? People often over-estimate their abilities in navigating through flood waters (both in cars and on foot).
  2. Wash your hands – if you have been exposed to contaminated water, keep your hands as clean as possible.
  3. Avoid injury when walking through flood water. Brown water may conceal sharp objects that can cause injury. Sturdy boots may help prevent cuts, while waterproof gear like fishing waders can protect open skin.
  4. Beware of downed power lines or chemical spills. When live electrical wires or power lines contact water, there is a risk of electrocution for those in contact with the water. Take caution and treat all electrical lines, wires, equipment and fixtures as if they are energized until proven otherwise.
  5. Beware of gas leaks. Immediately evacuate buildings if a gas leak or odor is detected.
  6. Keep wounds dry – Try not to get flood water in existing wounds, cuts, or scrapes. If the water is in contact with an open sore, wash it right away with soap and water and see a doctor immediately if it shows signs of infection such as increasing redness, warmth, pain, or pus.
  7. Keep kids out of the water – make sure they don’t play with toys that may have been in contact with the water, nor play in it.
  8. Extra vaccines aren’t really necessary. Although dirty water can spread cholera, malaria, and Hepatitis A, these are essentially non-existent in the United States. Tetanus lives on dry surfaces (not flood zones), so contrary to popular belief, vaccines are not urgently helpful post Irma and Harvey.
  9. Get out of wet clothes quickly. Rinse your body entirely after exposure to flood water to reduce your risk of infection or chemical injury.
  10. Seek medical attention immediately for any infections or unusual symptoms such as upset stomach or diarrhea. Flood waters may contain bacteria including E. coli, Vibrio species, Salmonella, or Shigella. Unfortunately, there are no vaccines for these infections.
  11. Mold proof your house. When you return home to a flood water damaged house, remove items that can promote mold growth (carpeting, wall paper, and clothing). Be sure to wear equipment like shoes, gloves, and an N95 dust mask when removing material that may contain mold.
  12. Check your pets. Dogs and cats don’t realize that flood water is contaminated and and are at high risk for infection. If your pet looks sick, take them to the vet as soon as possible for treatment.

If you have any more questions just Ask Hanna, our health advisors are here to help.


Dr. Val Jones MD – Health Tip Content Editor
Reviewed and Approved by Charles W. Smith MD, Medical Director on 9-13-2017
Image: ©Shutterstock / Scherbinator

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