Sometimes, microorganisms grow in the food that we consume. Food gets contaminated when such microorganisms multiply & release toxic substances, resulting in food poisoning.
Food poisoning can also be caused by the following three factors:
Bacteria: Bacteria is a major cause of food poisoning. Salmonella is the major cause of food poisoning in the US. Campylobacter & Clostridium botulinum are the other two lethal causes of food poisoning. Staphylococcus aureus is the most common agent causing food poisoning.
Viruses: The viruses responsible for food poisoning include norovirus, sapovirus, rotavirus, and astrovirus. Food poisoning by viruses is less common but proves to be very fatal. Hepatitis A virus is a serious condition transmitted through food.
Parasites: Food poisoning by parasites is also very rare. Toxoplasma, a common cause of food poisoning, can be present in cat litter boxes.