Foodborne illness, food poisoning and causative agents of foodborne illness

Foodborne illness (sometimes called “foodborne disease,” “foodborne infection,” or “food poisoning)Foodborne diseases are an important public health burden worldwide. There are an estimated 250 pathogens that can cause foodborne related illnesses. Centre for Disease Control (CDC) USA has reported 31 known agents of foodborne illness and rest are called “unspecified agents”Foodborne illness is defined as two or more cases of a similar illness resulting from ingestion of a common food.

It can result from consuming foods contaminated with various pathogens. In most cases bacteria are the major pathogen followed by viruses, then parasites. However, natural or manufactured chemicals and toxins from organisms can also cause foodborne illnesses.Symptoms of food poisoning include stomach upset, abdominal cramps, nausea and vomiting, diarrhea, fever, and dehydration. Symptoms may range from mild to severe.Foodborne Intoxications vs. Foodborne Infections

Foodborne intoxications are caused by the ingestion of toxins (natural/preformed bacterial/chemical) and the incubation period ranged from minute to hours.  Bacillus Cereus, Clostridium botulinum, Staphylococcus aureus are the common causes of Foodborne Intoxication

Live bacteria/virus/parasites are responsible for foodborne infections. They invade and multiply in the lining of intestine and incubation period varies from hours to days. Campylobacter jejuni, Listeria monocytogenes and Escherichia coli 0157:H7 are the major causes of Foodborne infections.

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Common pathogens causing food-borne illness are:

Bacteria

1.      Bacillus cereus

Ingestion of food contaminated with Bacillus cereus or toxins produced by this organism is responsible for foodborne illness. Bacillus cereus produces enterotoxins. It causes food poisoning of two types: diarrheal type, which is characterized by abdominal pain and watery diarrhea; and emetic type which is manifested by profuse vomiting.

2.      Campylobacter jejuni (but also C. fetus, Campylobacter coli)

3.      Clostridium perfringens

4.      Clostridium botulinum
Botulism is caused by a neurotoxin from Clostridium botulinum

5.      E.coli 0157:H7 (Enterohemorrhagic E. coli)

6.      Listeria monocytogenes

7.      Salmonella Typhimurium and S. Enteritidis

8.      Shigella spp
Shigellosis is also known as bacillary dysentery. Most cases are caused by Shigella sonnei. However, S. dysenteriae, S. flexneri and S. boydii can also cause foodborne related illnesses.

9.      Staphylococcus aureus
Staphylococcus aureus makes seven different toxins that are frequently responsible for food poisoning.

10.  Vibrio cholerae
Vibrio choleare produces cholera toxin. Which is an enterotoxin, responsible for profuse watery diarrhea (also termed as rice watery stools).

11.  Yersinia enterocolitica

Parasites

12.  Toxoplasma gondii
Toxoplasmosis is caused by an intracellular protozoan, Toxoplasma gondii, which can infect all species of mammals, including humans

13.  Cryptosporidium

14.  Cyclospora

Virus

15.  Adenovirus

16.  Rotavirus

17.  Calciviruses  (Better known as Norwalk virus)

18.  Norwalk-like virus (or Norovirus)