Food illness, more commonly referred to as food poisoning, is the result of eating contaminated, spoiled, or toxic food. The most common symptoms of food poisoning include nausea, vomiting, and diarrhea.

Infectious organisms- including bacteria, viruses and parasites- or their toxins are the most common causes of food poisoning.


Infectious organisms or their toxins can contaminate food at any point of processing or production. Contamination can also occur at home if food is incorrectly handled or cooked.


Food poisoning symptoms, which can start within hours of eating contaminated food can be mild and resolves without treatment, but dehydration and electrolyte abnormalities may develop.


Signs and symptoms of food poisoning


Food poisoning symptoms vary with the source of contamination. Most types of food poisoning cause one or more of the following signs and symptoms:

. Nausea

. Vomiting

. Watery or bloody diarrhea

. Abdominal pain and cramps

. Mild fever

. Loss of appetite

. Weakness

. Headaches


Symptoms of potentially life-threatening food poisoning include:

. Diarrhea persisting for more than three days

. A fever higher than 39 C

. Difficulty seeing or speaking

. Symptoms of severe dehydration, which may include excessive thirst, dry mouth, passing little to no urine, and difficulty keeping fluids down

. Blood urine


If you experience any of these symptoms, you should contact your doctor immediately.

Causes of food poisoning



Bacteria is by far the most prevalent cause of food poisoning. The most dangerous ones being E.coli, Listeria, and Salmonella. Campylobacter and C. botulinum(botulism) are two lesser-know and potentially lethal bacteria that can lurk in our food.


Food poisoning caused by parasites is not as common as food poisoning caused by bacteria, but parasites spread through food are still very dangerous. Toxoplasma is the parasite seen most often in cases of food poisoning. It’s typically found in cat litter boxes. Parasites can live in your digestive tract undetected for years. However, people with weakened immune systems and pregnant women risk serious side effects if parasites take up residence in their intestines.


Food poisoning can also be caused by a virus. The norovirus, also known as the Norwalk virus, causes a great number of cases of food poisoning each year. In rare cases, it can be fatal. Saporivus, rotavirus, and astrovirus bring on similar symptoms, but they’re less common. Hepatitis A virus is serious condition than can be transmitted through food.

Contamination of food

Pathogens can be found on almost all of the food that we eat. However, heat from cooking usually kills pathogens on food before it is consumed. Foods eaten raw are common source of food poisoning because they don’t go through the cooking process.


Occasionally, food will come in contact with the organisms in fecal matter. This most commonly happens when a person preparing food doesn’t wash their hands before cooking.

Meat, poultry, eggs, and dairy products are frequently contaminated. Water may also be contaminated with organisms that cause illness.


The most common serious complication of food poisoning is dehydration- a severe loss of water and essential salts and minerals.

Infants, older adults and people with suppressed immune systems or chronic illnesses may become severely dehydrated when they lose more fluids than they can replace. In that case, they may need to be hospitalized and receive intravenous fluids. In extreme cases, dehydration can be fatal.


The diagnosis of food poisoning is based on a detailed history, including how long you have been sick, your symptoms and specific foods you’ve eaten. Your doctor will also perform a physical exam, looking for signs of dehydration.


Depending on your symptoms and health history, you doctor may conduct diagnostic tests, such as a blood test, stool culture or examination for parasites, to identify the cause and confirm the diagnosis.


Treatment for food poisoning typically depends on the source of the illness, if known, and the severity of your symptoms. For most people, the illness resolves without treatment withing few days, though some types of food poisoning may last longer.

Treatment of food poisoning may include:

. Replacements of lost fluids. Fluids and electrolytes- minerals such as sodium, potassium and calcium that maintain the balance of fluids in your body- lost to persistent diarrhea need to be replaced.

. Antibiotics. Your doctor may prescribe antibiotics if you have certain kinds of bacterial food poisoning and your symptoms are severe. Food poisoning caused by listeria needs to be treated with intravenous antibiotics during hospitalization.

Prevention of food poisoning


To prevent food poisoning:

. Wash your hands, utensils and food surfaces often. Wash your hands well with warm, soapy water before and after handling or preparing food.

. Keep raw foods separate from ready- to- eat foods. When shopping, preparing food or storing food, keep raw meat, poultry, fish and shellfish away from other foods to prevent cross-contamination.

. Cook foods to a safe temperature. To safest way is to use a food thermometer.

. Refrigerate or freeze perishable foods promptly- withing two hours of purchasing or preparing them.

. Defrost food safely. Don’t flaw food at room temperature. The safest way to thaw food is to defrost it in the refrigerator.

. Throw it out when in doubt. If you aren’t sure if a food has been prepared, served or stored safely, discard it.



The above article serves only as reference. Kindly refer to your primary care provider for complete consultation and treatment.

For more details please send email to:


ADD: 396 Hongbaoshi Rd, Changning District, Shanghai, China