What Is the Causative Agent of Food Poisoning?

The cause may be a living organism, such as a bacterium, virus, or parasite, or a toxin already present in food. Contamination can happen during growing, processing, cooking, storage, or serving. Cross-contamination between raw and ready-to-eat foods is another route. The specific cause is not always identified, and symptoms alone cannot reliably distinguish one agent from another.

Food poisoning may cause abdominal pain, diarrhoea, fever, nausea, or vomiting. The illness can affect one person or several people who shared a meal. Symptoms may begin soon after exposure or later, depending on the organism or toxin. The key immediate concern is loss of fluid, especially when vomiting and diarrhoea occur together.

Take frequent small sips of water or use Oral Rehydration Therapy to replace fluid and salts. Rest, and choose light foods when you can tolerate them. Avoid preparing food for other people while you have vomiting or diarrhoea, and wash hands with soap and water. A clinician may recommend stool testing or treatment based on the symptoms, exposure, age, and health history. Do not use leftover antibiotics or anti-diarrhoeal medicine without medical advice.

Get urgent medical help for severe or worsening abdominal pain, bloody diarrhoea, repeated vomiting, inability to keep fluids down, fainting, confusion, very little urine, or signs of dehydration. Fever with marked weakness also warrants prompt assessment. Babies, older adults, pregnant people, and people with weakened immunity or long-term illness should seek advice early. If dehydration is severe, IV Fluid Therapy may be needed.

Ask what cause is most consistent with your exposure and symptoms, whether you need a stool test, how to replace fluids safely, when you can return to work or school, and how to protect other household members.