Both viruses and bacteria can cause food poisoning. Food poisoning can also be caused by parasitic protozoa, like Giardia lamblia. Food poisoning, which is sometimes called foodborne illness, is caused by eating foods that are contaminated with certain bacteria, viruses, and/or parasites. Not all symptoms of food poisoning are the same, because the specific symptoms are dependent on the germ that was ingested, and symptoms can take anywhere from hours to days to develop. The most common symptoms are upset stomach, stomach cramps, nausea, vomiting, diarrhea, and/or fever.
Let's look at a specific virus that causes food poisoning. Norovirus is a common virus that causes foodborne illness. Norovirus can enter the body in a variety of ways, but common food sources are leafy greens and fresh fruits. Symptoms usually begin anywhere between twelve and forty-eight hours and include diarrhea, nausea, vomiting, and stomach pain.
Salmonella is a common bacterial cause of food poisoning. Symptoms can begin anywhere from six hours to six days after exposure, and the symptoms are practically identical to norovirus. Consuming raw or undercooked poultry is a common source of salmonella. Raw eggs are also a source of the bacteria, in addition to various raw fruits and vegetables.