As many as 60 people in both Canada and the United States have fallen ill, and 2 have died, after consuming what is believed to be E. coli tainted romaine lettuce.

According to the CDC (Centers for Disease Control and Prevention), the E. coli infections have occurred in 13 different states including California, Connecticut, Illinois, Indiana, Michigan, Nebraska, New Hampshire, New York, Ohio, Pennsylvania, Virginia, Vermont, and Washington. The Public Health Agency of Canada says Canadian provinces affected by the outbreak include Ontario, Quebec, New Brunswick, Nova Scotia, and Newfoundland and Labrador.

While no new cases have been reported since December, and with Health Canada saying the risk of developing E. coli is now considered low, some major grocery stores and restaurant chains have chosen to pull romaine lettuce from their menus and store shelves as a precautionary measure. In Atlantic Canada, these restaurants include Boston Pizza, Swiss Chalet, Milestones, East Side Mario’s, and New York Fries; while Sobeys Inc. says they have removed over 300 products from store shelves across all Canadian provinces, including Safeway, Thrifty Foods, IGA, Foodland, FreshCo and Lawton’s Drug Stores.

Because lettuce is usually consumed as a raw vegetable, it is much easier for E. coli to develop if it is not washed properly. Lettuce can become contaminated during harvesting, from handling, as well as storage and transportation. Dr. Ali Ghahary, a family physician practicing in the city of Vancouver, says it’s crucial to not only wash your hands, but to also wash fruits and vegetables – including lettuce – before eating them, by using warm or hot water. When handling food you should also make sure there’s no potential for cross-contamination with things like meats or other fresh produce, as E. coli can be easily transferred. Things like utensils and cutting boards can also cause cross-contamination.

It may take as little as 1 day or as many as 7 days for symptoms of an E. coli infection to develop. Milder symptoms include abdominal pain/cramping, gas, sudden or severe diarrhea, loss of appetite, nausea and vomiting. These symptoms can last anywhere from a few days to an entire week. Someone infected with E. coli may also experience pale skin, have a decreased urine output, bloody urine, fatigue, dehydration, and fever. These symptoms are considered severe and you should seek immediate medical attention if you are experiencing any of them.

Diagnosing E. coli is fairly easy, as it can be found by doing a simple stool test. In most cases symptoms of an E. coli infection will go away on their own if you get rest and drink plenty of water. However, you may also require further treatment such as fluids given intravenously, as well as antiemetic medications to reduce the nausea and vomiting. Anti-diarrheal medication should be avoided as it can slow the digestive system down, which then prevents your body from being able to get rid of the toxins.