If so, and you were not gone more than 4 to 5 hours, the food is usually still safe to eat. If in doubt, discard. Some items are safe to take on a picnic without refrigeration. Food Poisoning Food poisoning is a general term that is used to describe illnesses that have been contracted while consuming contaminated food or water. A number of microorganisms including bacteria, viruses, parasites and fungi can be responsible for food poisoning.
Illness can also result from toxins that are released by the microorganisms themselves.
It is estimated that between 6 and 7 million people contract some type of foodborne illness, or food poisoning, each year in the United States. Cases of foodborne illness tend to go underreported, because many people assume that they have the flu and do not visit a doctor. Typical symptoms of foodborne illness include nausea, vomiting, diarrhea, fever and abdominal cramps. Other, more severe symptoms may include paralysis, visual changes and difficulty swallowing. Symptoms usually appear 4 to 48 hours after ingestion of a contaminated food but they can be delayed for as long as 2 weeks.