Salmonella are a group of bacteria that is commonly found in the intestines of animals and birds. The bacteria can be transmitted to people when they eat foods contaminated with animal feces. Often, contaminated foods are of animal origin, such as beef, poultry, milk or eggs; however, all foods, including fruits and vegetables, can become contaminated.
People who eat food contaminated by Salmonella can become ill with salmonellosis. Symptoms of salmonellosis can include diarrhea, vomiting, stomach cramps and fever.
Eating contaminated foods is the most common cause of infection with Salmonella bacteria. Contaminated foods could include raw or under cooked eggs or egg products, meat, poultry, raw fruit and vegetables.
You can also be exposed to Salmonella bacteria by not thoroughly cleaning surfaces that have been used to prepare raw meat and other foods in the kitchen, or if you have not properly washed fresh fruits and vegetables before eating them. Food handlers who have not thoroughly washed their hands after handling raw meat or after using the washroom can also contaminate food.
Salmonella can also be spread to people through contact with infected animals, including reptiles, amphibians, pocket pets (hedgehogs, rodents), birds, livestock, and dogs and cats. These animals may carry the bacteria even when healthy. Pet foods (raw or processed, wet or dry) can also be contaminated with Salmonella bacteria, and can increase a pet’s chance of shedding Salmonella. You can become infected if you do not wash your hands after touching your pets or handling their food.
If you are infected with the bacteria you may not get sick or show symptoms, but you can carry the bacteria and spread the infection to others.
Like other foodborne illnesses, the symptoms of salmonellosis mainly involve the gut.
Symptoms include sudden onset of:
Salmonellosis symptoms generally occur within 6 to 72 hours after ingesting the bacteria in food, water or other environmental sources, and last 4 to 7 days.
People who are infected with Salmonella bacteria can be infectious from several days to several weeks. However, some people can become infected with the bacteria and not get sick or show symptoms. Even though you don’t show symptoms, it is still possible to carry the bacteria and spread the infection to others.
Raw meat, poultry and eggs that are contaminated with Salmonella and have not been cooked properly are the most common sources of illness. The following foods have also been associated with salmonellosis:
Some people are more susceptible to infection than others. Seniors and those with weakened immune systems may be unable to fight off the infection, and can get sick more easily than others. These people are also at a higher risk of serious illness from salmonellosis.
Most people who become ill from Salmonella bacteria will recover fully after a few days.
In severe cases, salmonellosis can cause serious illness and sometimes death. Seniors and those with weakened immune systems are at higher risk of serious illness. An example of severe illness could be septicaemia (also known as blood poisoning).
In rare cases, severe complications can occur. Some people may experience chronic symptoms, such as reactive arthritis (Reiter's Syndrome) three to four weeks later.
There are many different illnesses that cause the same symptoms as salmonellosis. The only way to diagnose it is through laboratory tests on the stools of infected people. Once Salmonella has been identified, further testing can determine the type of Salmonella and the appropriate treatment.
Treatment for those infected with Salmonella should include drinking plenty of liquids to replace the body fluids lost through diarrhea and vomiting. This is particularly important for seniors, children and those with weakened immune systems. In severe cases, patients may need to be given fluids intravenously.
In rare cases, Salmonella may spread from the intestines to the blood stream and other organs, causing severe illness and possibly even death in vulnerable people. In severe cases patients may require treatment with antibiotics; however, some Salmonella bacteria have become resistant to many commonly used antibiotics.
Hand washing is one of the best ways to prevent the spread of foodborne illness.
It is also important to ensure you thoroughly cook foods to destroy bacteria. Contaminated foods may look and smell normal.
The following tips will help you reduce your risk of infection with Salmonella bacteria or other foodborne illnesses:
If you think you are infected with salmonellosis or any other foodborne illness, do not prepare food for other people unless you wear disposable gloves and follow safe food handling procedures.
Yes, the Public Health Agency of Canada works with the provinces and territories to track the number of cases of salmonellosis across the country.
When people get sick and go to the doctor, those doctors in many cases take samples from the patients and send them to a provincial, territorial or federal lab for testing.
Those labs test the samples to identify the genetic fingerprint of the bacteria, virus or parasite responsible for the illness.
The lab then posts the results for bacterial illnesses on PulseNet Canada, a national network that allows microbiologists to track and share genetic fingerprints for comparison across the country.
All labs then compare their results with those posted on PulseNet to find matches and identify outbreaks.
PulseNet Canada is coordinated by the Public Health Agency of Canada’s National Microbiology Laboratory in Winnipeg.
Foodborne illnesses are relatively common in Canada. The Public Health Agency of Canada estimates that about 4 million Canadians suffer from a food-related illness each year.
Salmonellosis is the second most frequently reported food-related illness in Canada. Many of these illnesses are sporadic cases, but some are part of outbreaks.
A case refers to illness in one person whereas an outbreak refers to two or more people linked by a common exposure within a specific time frame.
A national outbreak occurs when illness is linked in two or more provinces or territories.