Bacterial Food Poisoning

According to the Center for Disease Control and Prevention, food poisoning is the cause for about 76 million illnesses, 3,25,000 hospitalizations, and up to 5,000 deaths every year. Food poisoning is a common illness that occurs immediately after consuming contaminated food or drinks. Although generally a mild condition, it can also result in death.

This illness reveals itself in the form of diarrhea, vomiting, fever, chills, dehydration, bloody stools, etc. It can be caused by infectious agents such as bacteria, parasites, or even viruses. Moreover, it can also be caused by toxic agents like poisonous mushrooms, pesticides on fruits and vegetables, or improperly cooked foods. Improperly handled, packaged, or stored foods also lead to food poisoning.

What is Bacterial Food Poisoning?

Bacteria dwelling in the intestines of infected humans or pets, poultry, cattle, etc., can cause diarrhea in humans. Their feces can contaminate recreational water, drinking water, soil, meat during slaughter, etc. Not washing one’s hands after using the washroom also results in this condition. Ear, throat, nose, and urinary infections can also result in food poisoning. Moreover, consuming undercooked beef, shellfish, raw eggs, raw milk (not pasteurized), non-adequately stored or cooled food, can also result in bacterial food poisoning.


Symptoms will begin to appear about 48 hours after consumption of contaminated food. The symptoms that may occur are as follows:

Nausea and occasional vomiting
General malaise with fever (occasionally)
Diarrhea (loose or watery stools)
Abdominal cramps

These were some mild food poisoning symptoms. Severe diarrhea can lead to dehydration, tiredness, sunken eyes, thirst, and decreased urination.

In bacterial food poisoning, the bacteria spearheads inflammation of the stomach, small intestine, colon, or rectum. This inflammation reduces the amount of nutrients and water absorbed in the small intestine, thereby, resulting in diarrhea. Severe cases of infection can lead to ulcers and in some extreme cases, bacteria can even enter the blood and affect other organs of the body.

Common Bacteria Involved in Food Poisoning

Staphylococcus aureus
Food poisoning due to this bacteria occurs mainly by consuming foods that involve bare hands preparation, such as in salads, sandwiches, etc. When such food items are left at room temperature for a long period of time, bacteria grow and produce toxins. Maintaining good personal hygiene and refrigeration of food items will keep bacterial invasion at bay.

Salmonella is passed to humans from animals (poultry and pets). It is commonly caused by consumption of unpasteurized milk or undercooked poultry, meat, or eggs. Bacteria can spread from the intestine to other organs of the body.

Clostridium botulinum
This bacteria is responsible for one in every 400 cases of food poisoning in the US. Clostridium botulinum can exist as heat-resistant spores that grow and produce neurotoxins in processed, home-canned food products. The toxin produced by this bacteria can be destroyed by boiling the food for 10 minutes.

Campylobacter jejuni
This bacteria attacks those with a weak immune system, and at times even causes arthritis, brain and nerve problems, etc., besides food poisoning.

This bacteria is mainly found in soil and water. Vegetables growing in contaminated soil can be vectors of this bacteria. They are found in several types of uncooked meats and vegetables. Processed food like soft cheese and cold cuts can also get contaminated after processing.

Shigella (traveler’s diarrhea)
The bacteria is transmitted through feces and may cause dysentery and severe diarrhea. Unhygienic conditions in highly populated areas form breeding grounds for these bacteria.

Vibrio parahaemolyticus, Bacillus cereus, Clostridium perfringens, Yersinia enterocolitica, and Escherichia coli can also cause bacterial food poisoning.

Mild form of food poisoning usually subsides on its own within 2-3 days. During this time, the patient is advised to drink lots of water in order to prevent dehydration. Severe cases of diarrhea call for stool culture tests, since the tests will determine the kind of antibiotic treatment required. Presence of leukocytes and mysterious blood can be signs of bacterial invasions and need to be treated with antibiotics.