Food Poisoning: Symptoms, Causes, Treatment, and Prevention Tips

What Is Food Poisoning?

Food poisoning, or foodborne illness, occurs when you eat contaminated food or drink. It is caused by harmful bacteria, viruses, or parasites that infect your digestive system. Common causes include bacteria like Salmonella, E. coli, and Listeria, and viruses such as norovirus. Symptoms often include diarrhea, stomach cramps, nausea, vomiting, and sometimes a fever. These symptoms can appear anywhere from 30 minutes to three weeks after eating contaminated food.

Differentiating food poisoning and stomach flu

Food poisoning (foodborne illness) is often confused with stomach flu (gastroenteritis). While both are illnesses that affect our digestive system, they have different causes, symptoms, and durations. Food poisoning typically results from contaminated food, whereas stomach flu is more commonly triggered by viral infections.

Food poisoning (foodborne illness)

Stomach flu (Gastroenteritis)

Majority of cases result from ingesting or consuming contaminated food or drink.
Contamination can occur at various stages of the food production process – processing, distribution, preparation.
Examples of bacteria: Salmonella, Clostridium perfringens, Campylobacter, Vibrio, Staphylococcus aureus, Norovirus, Clostridium botulinum, Listeria, or Escherichia coli (E. coli).
Bacteria can quickly grow in food that is left at room temperature for too long. Reheating or boiling the food may not always render it safe, as some bacteria can produce toxins that heat cannot destroy. Once ingested, the bacteria continue to grow in the digestive system, causing an infection.

Most commonly triggered by viral infections, like norovirus or rotavirus. Although bacteria or parasites can also be responsible, viral infections are the most common cause.
Spreads by eating or drinking contaminated food or water, coming into contact with contaminated surfaces, or an infected person.
More contagious compared to food poisoning.

Symptoms of Food Poisoning

Food poisoning symptoms can show up at different times. Most often, people get sick within one to three days, but it is possible to feel ill as soon as 30 minutes or as long as three weeks after eating bad food. The exact timing depends on the type of bacteria or virus that caused the illness.

The severity of the symptoms differs from person to person, ranging from mild to severe. The symptoms can last for a few hours or several days. The duration of symptoms can also differ, lasting anywhere from a few hours to several days.

Common food poisoning symptoms include:

Fever
Watery or bloody diarrhea (sometimes bloody)
Headache
Nausea and vomiting
Stomach cramps

It is important to recognise these signs of foodborne illness to seek treatment early, especially if symptoms worsen or persist for more than a few days.

Signs to see a doctor

See a doctor right away if you are experience:

Bloody diarrhea
Diarrhea lasting more than three days
Persistent high fever over 38.9°C
Severe food poisoning
Difficulty keeping liquids down due to frequent vomiting

Watch for signs of dehydration, including:

Dry mouth
Dizziness
Infrequent urination

Untreated, severe dehydration can lead to serious health issues.

Potential Complications of Food Poisoning

The most common complication of food poisoning is dehydration. This occurs when the body loses more fluids and electrolytes than it can replace to work properly. It is especially dangerous for kids, older people, and those with weak immune systems. If dehydration is not treated quickly, it can lead to serious health problems that might even be life-threatening.

Other potential complications include:

Sepsis: A life-threatening condition where the body’s immune system responds severely to an infection, often leading to organ failure. Sepsis is a medical emergency and can be fatal if not treated aggressively.
Haemolytic Uremic Syndrome (HUS): A rare, severe complication caused by E. coli infections that results in the destruction of red blood cells and can ultimately lead to kidney failure.
Guillain-Barré Syndrome: A rare neurological disorder triggered by bacterial infections like Campylobacter. In this condition, the immune system attacks the body’s nerves, leading to muscle weakness and, in severe cases, paralysis.

Recognising these potential complications early is crucial in managing foodborne illness effectively, ensuring that prompt medical intervention prevents serious health issues.

Diagnosis and Treatment Options for Food Poisoning

Food Poisoning Diagnosis

Diagnosing food poisoning involves reviewing the patient’s symptoms, medical history, and occasionally doing laboratory tests, to identify the pathogen causing the illness. Early and accurate diagnosis helps guide appropriate food poisoning treatment and prevent complications like severe dehydration and sepsis.

Stool sample analysis	This test is done if the illness is severe, persistent, or if there is blood in the stool. The test result can identify the exact bacteria, viruses, or parasites that are causing the illness.
Blood tests	To detect signs of inflammation or infection and to identify more serious complications such as sepsis, kidney damage, or dehydration.
Food testing	More commonly done in outbreak situations and public health investigations. Samples of suspected food are tested to determine the contaminant, trace the source of contamination, and identify the specific pathogen involved in order to prevent further cases.
Specific testing	More specialised testing might be necessary for particular toxins, like botulinum toxin, or specific kinds of fish or shellfish poisoning.

Food Poisoning Treatment

The main goals of food poisoning treatment are symptom relief and dehydration prevention. Most cases of food poisoning usually go away on their own in a few days, but in more severe cases, medical intervention might be necessary to manage food poisoning symptoms and prevent complications like severe dehydration.

Medication	Antibiotics: For food poisoning caused by bacteria. Antidiarrheal (loperamide): For severe diarrhoea, to be used under a doctor’s supervision. Antiemetics (ondansetron): To help ease nausea and vomiting. Antipyretics or pain relievers (paracetamol): To help reduce fever and discomfort.
Dietary adjustments	Eat bland foods like rice, toast, crackers, and bananas while recovering. Avoid processed, fried, and dairy products.
Hydration	Replace lost fluids and electrolytes with lots of water, clear broths, and oral rehydration solutions (ORS). Avoid sweetened beverages, soft drinks, coffee, and tea. Intravenous (IV) fluids may be given in a healthcare facility setting for severe dehydration.

Prevention Tips for Food Poisoning

Preventing food poisoning starts with simple but effective steps. Follow these essential guidelines to protect yourself and your family from harmful bacteria and viruses.

Basic hand hygiene	Wash your hands thoroughly after sneezing or coughing, blowing your nose, interacting with animals, going to the toilet, and changing diapers. Good hand hygiene is crucial in preventing food poisoning caused by foodborne bacteria or viruses.
Food and drinks to avoid	Avoid unpasteurised milk, which may contain harmful pathogens.. Food that contains raw or undercooked meat, poultry, and eggs, as these can be contaminated with harmful bacteria like Salmonella or E. coli, increasing the risk of food poisoning.
Food preparation guidelines	Wash your hands with soap before and after handling raw produce or raw foods. All fruits and vegetables must be washed properly before consuming. Use plastic cutting boards for raw meat, poultry, or fish. All utensils and surfaces involved in preparing food should be thoroughly cleaned with soap and water before and after use. Ensure that food is cooked for a proper length of time and to a proper internal temperature.
Food storage guidelines	Leftovers should be frozen or refrigerated right away. To prevent cross-contamination, fruits, vegetables, cooked foods, and prepared foods should be kept apart from raw meat and raw eggs in storage. Keep salad dressings and mayonnaise, as well as any foods containing them, refrigerated. If you are not sure how long the food has been left out of the refrigerator, throw it away. If the food has been left out at room temperature for more than two hours, it is considered unsafe to eat. Throw away the food if you are not sure if it has gone bad.

Schedule an appointment for Food Poisoning Treatment at Gleneagles Hospitals

If you are experiencing symptoms of food poisoning, please consult our doctors. The expert team of Gastroenterologists at Gleneagles Hospitals is available for consultation to provide top-notch care and support.

Contact us to make an appointment today if you have any concerns or questions about food poisoning or other digestive health conditions. We guarantee the highest level of care, customised to meet your individual needs.

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