Salmonella is a pathogenic, or disease causing bacteria responsible for salmonellosis, a type of food poisoning. Commonly referred to by its genus, Salmonella is divided into two species, Salmonella enterica and Salmonella bangori. S. enterica is divided into six subspecies. S. bangori was originally designated a subspecies of S. enterica, but was later designated as its own species.
Salmonella is gram-negative rod-shaped bacteria with flagellum to aid in locomotion. Salmonella bacteria synthesize a capsule, enabling it to pass through the digestive tract. Researchers conclude that it takes over 1,000,000 Salmonella bacterium to cause infection. Fever and diarrhea are a result of the damage done to the intestinal lining. The Salmonella bacteria are passed in the feces of infected humans and animals.
Salmonella prefers low oxygen or oxygen-free environments. Salmonella takes residence in the human gastrointestinal tract, where it reproduces. Salmonella infections in humans are caused by consuming infected food, water, or by poor hygiene after handling animals.
In 2006, there were 121 Salmonella outbreaks reported to the Center for Disease Control (CDC). The outbreaks were tied to contaminated peanut butter and tomatoes. Many mild cases go unreported, so the CDC estimates that there are at least 30 times the number of reported cases each year. Symptoms include nausea, vomiting, diarrhea, stomach cramps, and fever.
