Salmonella FAQs

Frequently asked questions about salmonella.

What is salmonella?

That should be — what are salmonella? They're bacteria that can wreak havoc with your intestines. Salmonella normally live in the intestinal tracts of animals and birds. They usually get transmitted to people when we eat food contaminated with animal feces.

Salmonella can also be transmitted from people to animals.

Quick tip

Cleaning and sanitizing your countertops, cutting boards and utensils can go a long way towards protecting you from salmonella illness.

Try this homemade sanitizer: Combine 5 ml (1 tsp) of bleach with 750 ml (3 cups) of water in a labelled spray bottle. After cleaning, spray sanitizer on the surface/utensil and let stand briefly. Rinse with lots of clean water, and air dry (or use clean towels).

Most contamination occurs in beef, poultry, milk or eggs. Between May and mid-July 2010, nearly 2,000 people in the United States fell ill from a salmonella outbreak at an Iowa producer, leading to the recall of 380 million eggs. 

But contamination can also occur in fruits and vegetables, especially those that grow close to the ground. Fruits or vegetables may be tainted if handled by someone already infected, if they come in contact with animal manure, or through bad water or substrate.

Processed food can also be contaminated in the production stage. On March 4, 2010, the U.S. Food and Drug Administration announced a recall of dips and snack foods containing hydrolyzed vegetable protein (HVP), which is used as a flavour enhancer in processed foods. Traces of salmonella were found in equipment at a plant in Las Vegas, Nevada, which may have contaminated the HVP. The Canadian Food Inspection Agency also recalled dozens of products that may have been affected.

In July 2008, U.S. officials — after focusing on tomatoes as a possible source of contamination — traced a salmonella outbreak that sickened more than 1,300 people to a batch of serrano peppers shipped from a Mexican farm.

Every year, 6,000 to 12,000 cases of salmonella illness are reported. But the actual number of cases is believed to be much higher. Mild cases often go unreported, or are called the "stomach flu."

Salmonella can also taint one of our greatest food pleasures: chocolate. On Nov. 12, 2006, Hershey Canada pulled 25 varieties of chocolate bars off store shelves because an ingredient at its Smith Falls, Ont., plant was contaminated with salmonella.

In January 2009, a salmonella outbreak prompted U.S. officials to issue a recall of peanut butter. Canada's food watchdog has also pulled certain snack foods containing peanut butter for fear of contamination. ((Minnesota Department of Health/Associated Press))

In Britain, Cadbury recalled one million chocolate bars after a salmonella outbreak. The problem was traced to a leaky pipe in one of its factories in June 2006.

Chocolate has lots of sugar and fat, giving salmonella an ideal place to grow and thrive. That fat and sugar also helps the salmonella survive the acid bath in your stomach. That means it takes less of the nasty bug in chocolate to make you sick than it does in meat or dairy products.

How do I get infected?

Salmonella bacteria are present in a lot of the meat, poultry and eggs that you buy at your local store. Proper cooking will kill the bacteria, but sometimes you need to do a little more during food preparation to safeguard yourself. The bacteria could be present on eggshells, for example. If you use raw eggs in some of your recipes, you might want to thoroughly wash the eggs before you crack them.

Fresh fruits and vegetables may also contain salmonella bacteria on their surfaces. There have been salmonella outbreaks reported in Canada in recent years involving bean sprouts, cantaloupes and mushrooms. Proper washing — or cooking — should keep your food safe.

What is salmonella typhi?

Salmonella typhi is the bacteria that leads to typhoid fever, a serious condition that affects an estimated 12.5 million people each year and causes about 600,000 deaths.

Fewer than 500 cases are reported in Canada and the U.S. each year. It’s usually contracted by people travelling abroad.

S. Typhi is a far more dangerous form of salmonella than the bacteria found in spoiled food, and most recently in eggs in the U.S.

It’s spread through the feces or urine of an infected person. Poor food handling practices and lack of hygiene are usually responsible for outbreaks.

Once the bacteria is ingested it multiplies in the small intestine over a period of one to three weeks, and then begins to spread through the body into other organs, overwhelming the body’s natural defenses. If treated, less than one per cent of cases lead to death. In untreated cases 12 to 30 per cent of victims die.

According to the World Health Organization the last major outbreak occurred in the Congo in 2005, leading to 42,000 cases and 214 deaths.

Another source of salmonella can be unpasteurized dairy products like raw milk or unpasteurized cheeses.

You can also cross-contaminate your food. If you're slicing raw chicken for your stir-fry, thoroughly clean your cutting board before chopping your vegetables — or use another cutting board.

A stuffed turkey can be a salmonella disaster waiting to happen. The stuffing and the turkey normally reach safe temperatures at different times. Consider cooking the stuffing separately from the turkey. Sometimes it's not your fault. Food handlers who do not thoroughly wash their hands after handling raw meat or after using the bathroom can also contaminate your food.

Salmonella can be found in the feces of some pets, especially those with diarrhea. Snakes, turtles and reptiles may carry salmonella even when they're healthy. If you keep any of them as pets, you'll have to take extra care after handling them.

How do I know if I've been infected?

Suffering from diarrhea, fever and/or cramps? Well, there's a good chance you ate something that contained salmonella bacteria within the previous 12 to 72 hours. Other symptoms include nauseau, headache and vomiting.  Get ready for four to seven days of not feeling very well at all.

Is there a cure?

Time. As with any illness that involves vomiting or diarrhea, you need to take in plenty of fluids to replace those that you lose. If you don't, you run the risk of dehydration.

In some cases, salmonella can spread from the intestines to the blood stream and other parts of the body, causing severe illness. In those cases, antibiotics are sometimes effective, although some salmonella bacteria have become resistant to many commonly used antibiotics.

Who's at risk?

Young children, seniors and those with weakened immune systems from diseases such as AIDS, or as a result of some cancer treatments, are the most vulnerable. In severe cases, salmonella can kill.

How can I minimize my risk?

Here are a few tips: 

  • Contaminated foods may look and smell normal. Thorough cooking kills the bacteria.
  • Don't eat raw or undercooked eggs, poultry or meat. You might want to think twice about using raw eggs in some of your homemade sauces and salad dressings. Try using pasteurized egg products.
  • If your poultry or meat is pink in the middle, your chances of contracting salmonellosis will be higher.
  • Avoid serving raw or unpasteurized milk and cheese made from raw or unpasteurized milk — especially to young children, pregnant women, the elderly and people with weakened immune systems.
  • Thoroughly wash fruits and vegetables before eating them.
  • Keep meats separate from fruits, vegetables, cooked foods and ready-to-eat foods — both in the shopping bag and in your refrigerator.
  • Bacteria grow quickly at room temperature. Get your perishable food into the refrigerator as quickly as possible, especially during the warmer months of the year.
  • Always defrost food in the refrigerator, in cold water or in the microwave, never at room temperature. Set your refrigerator to 4 C (40 F) and your freezer to –18 C (0 F).
  • Wash your hands before handling any food. Be sure to wash your hands, cutting boards, counters, knives and other utensils after preparing uncooked foods.
  • Got salmonellosis? Don't prepare food or pour water for anyone until you're clear of the bacteria.
  • Own cats or dogs? Wash your hands after cleaning the kitty litter or stooping and scooping after your dog.
  • Always wash your hands after handling your pet reptiles. There have been salmonella warnings issued on pet turtles.
  • If you are diagnosed with salmonellosis, be sure that you or your doctor informs the local public health department. You may be part of a wider outbreak that the general public should know about.