Annapolis, Maryland, flooded after Hurricane Isabel in 2003. Susan Walsh / AP

A new study suggests that extreme weather is associated with higher risk of foodborne illness. Here’s how to keep yourself safe.

Add this to the list of woes linked to climate change: increased risk of Salmonella infection. A new University of Maryland study found that extreme temperature and precipitation events—like the storms, floods, and heat waves we’ve seen this summer—are associated with a higher risk of contracting salmonellosis, especially in coastal communities. That’s a serious cause for concern, as global warming brings more volatile weather patterns worldwide.

The study, published in the journal Environment International, focused on 24 counties in Maryland. From 2002 to 2012, the researchers observed that extreme heat events were associated with a 4.1 percent increase in salmonellosis risk, and extreme precipitation events with a 5.6 percent increase in salmonellosis risk. The impact was “disproportionately felt in coastal areas.”

Why are coastal communities at greater risk? It could be because they’re hit harder by extreme weather, which tends to produce conditions conducive to Salmonella growth and proliferation. The bacteria thrive in warm, wet environments and can survive up to 405 days in soil after manure is applied. Flooding can carry these pathogens—often from wastewater treatment plants, septic systems, and animal feed operations—to wells and recreational water. (This is one of the major dangers of combined sewer overflows.) People who live in coastal areas typically have more exposure to these potential sources of Salmonella contamination.

Bottom line: You don’t have to eat Salmonella-contaminated chicken to get sick. You could just swim downstream from the chicken farm.

Public health officials will have to take this increased risk into account as global temperatures continue to rise. The study’s authors write that the higher intensity and frequency of today’s severe weather events “will have a direct impact on the overall burden of infectious diseases such as salmonellosis.” Moreover, the growing population in coastal areas—expected to reach almost 150 million in the U.S. by 2020—may require a targeted response.

How to decrease your risk

No matter where you live, you can follow these tips from the CDC, USDA, and the Minnesota Department of Health to prevent Salmonella infection:

In the kitchen:

  • Always cook meat, poultry, and eggs thoroughly.
  • Do not eat or drink foods containing raw eggs—yes, that includes cookie dough—or raw (unpasteurized) milk.
  • Keep raw meat and poultry separate from produce and other foods when shopping for and storing groceries.
  • Wash hands, kitchen work surfaces, and utensils with soap and water immediately after handling raw meat or poultry.
  • Be particularly careful with foods prepared for infants, the elderly, and the immunocompromised.

Eating or cooking outside:

  • Do not eat food in areas where animals are present.
  • When taking food off the grill, use a clean platter. Don't put cooked food on the same platter that held raw meat or poultry.
  • In hot weather (above 90 °F), food should never sit out for more than 1 hour.
  • Refrigerate leftovers promptly in shallow containers. Discard any food left out more than 2 hours (1 hour if temperatures are above 90 °F).

In recreational waters such as swimming pools and water parks:

  • Stay out of the water if you have diarrhea.
  • Shower before you get in the water.
  • Don’t pee or poop in the water.
  • Don’t swallow the water.

Also, be sure to wash hands with soap and water after handling reptiles, birds, or baby chicks, and after contact with pet feces.

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