Think You Got Food Poisoning? What to Do and How to Report It

Symptoms and timing

Foodborne illness most often causes nausea, vomiting, diarrhea and stomach cramps, sometimes with fever. How quickly symptoms start depends on the germ. Toxins from bacteria such as Staphylococcus aureus can cause vomiting within one to six hours. Norovirus, the most common cause of foodborne illness, usually starts 12 to 48 hours after exposure. Salmonella can take anywhere from six hours to six days, Campylobacter two to five days, and Listeria can take weeks.

This matters because the meal you ate just before getting sick is often not the one that caused it. When you think back, consider everything you ate in the previous few days, not just the last meal.

When to see a doctor

Most cases of food poisoning clear up on their own within a few days. Public health agencies such as the U.S. Centers for Disease Control and Prevention advise seeing a health care provider if you have bloody diarrhea, a fever above 38.9 °C (102 °F), diarrhea lasting more than three days, vomiting so often that you cannot keep liquids down, or signs of dehydration such as very little urine, a dry mouth or dizziness when standing.

People at higher risk of serious illness should be quicker to get care. That includes pregnant people, young children, adults over 65, and anyone with a weakened immune system. Listeria in particular can be dangerous during pregnancy even when the parent's symptoms are mild.

Looking after yourself and others

The biggest risk for most people is dehydration, so keep drinking small amounts of fluid often. Oral rehydration solutions from a pharmacy replace lost salts better than water alone. Avoid preparing food for other people while you are sick and for at least two days after your symptoms stop, and wash your hands thoroughly after using the toilet. Norovirus in particular spreads very easily within households.

If you work in a restaurant, child care or health care setting, tell your employer. Food workers with vomiting or diarrhea are generally required to stay off work until they have been symptom-free for a set period, often 24 to 48 hours.

Write it down and keep the evidence

While it is fresh, write down where and when you ate over the past few days, what you ordered, who you ate with and whether they got sick, when your symptoms started, and what they were. Keep receipts or card statements, which can confirm the date and time of a meal.

If you still have leftovers you suspect, wrap them, label them "do not eat", and keep them in the fridge in case public health wants to test them. If a doctor offers a stool test, it is worth doing: a lab result identifying the germ is one of the most useful pieces of information for an investigation.

How to report a suspected foodborne illness

In Canada, contact the public health unit or regional health authority for the area where you ate. Most have a phone line or online form for food complaints and suspected illnesses, and in some cities, such as Toronto, you can start with 311. In the United States, contact your city or county health department; New York City also takes reports through 311, and many state health departments have online forms. Our region pages link to the official site of each health authority whose data we carry.

Give as much detail as you can: the business name and address, the date and time you ate, what you ate, your symptoms and when they started, whether anyone else got sick, and whether you saw a doctor or had a test. You do not need to be certain that a particular place made you sick to report it.

Why reporting matters, even for a mild case

Most people with food poisoning never report it, which is why outbreaks can go unnoticed. Public health staff look for patterns: two or three unrelated people describing similar symptoms after eating at the same place is often how an outbreak is first detected. Lab results add to this. When a stool sample identifies a germ, its genetic fingerprint can be matched with other cases, sometimes linking illnesses across cities.

A report can lead to a complaint inspection of the business, sampling of food, interviews with other diners, and instructions to the operator to fix the problem. You may not hear the outcome directly, but any inspection that results will appear in the public record.

Checking a restaurant's record afterwards

Looking up the place where you ate can help you understand what may have happened, though a clean record does not rule it out and a poor one does not prove it. Look for higher-risk findings such as temperature control, handwashing and cross-contamination, and whether they repeat across inspections. If a complaint or follow-up inspection appears soon after your visit, that is usually where any problems found would be recorded.