Salmonella is a bacterium that causes one of the most common enteric (intestinal) infections in the United States: Salmonellosis. Today, the number of known strains of Salmonella totals over two thousand.
The term Salmonella refers to a group or family of bacteria that variously cause illness in humans. Salmonellaserotype typhimurium and Salmonella serotype enteritidis are the most common in the U.S. Salmonella Javiana is the fifth most common serotype in the U.S and accounted for 3.4 percent of Salmonella isolates reported to the CDC during 2002.
Most Salmonella infections are caused by eating contaminated food, especially food from animal origins. One study found that 87 percent of all confirmed cases of Salmonella were foodborne, with 10 percent from person-to-person infection and three percent caused by pets.
Salmonella infections can result in a broad range of illness, from no symptoms to severe illness. The most common clinical presentation is acute gastroenteritis. Symptoms include diarrhea and abdominal cramps, often accompanied by a fever of 100°F to 102°F (38°C to 39°C). Other symptoms may include bloody diarrhea, vomiting, headache, and body aches. The incubation period, or the time from ingestion of the bacteria until the symptoms start, is generally six to 72 hours; however, there is evidence that in some situations the incubation can last longer than 10 days. People with salmonellosis usually recover without treatment within three to seven days. Nonetheless, the bacteria will continue to be present in the intestinal tract and stool for weeks after recovery of symptoms — on average, one month in adults and longer in children.
Salmonella infections usually resolve in three to seven days and often require no treatment. Persons with severe diarrhea may require rehydration, often with intravenous fluids. Antimicrobial therapy (or treatment with antibiotics) is not recommended for uncomplicated gastroenteritis. In contrast, antibiotics are recommended for persons at increased risk of invasive disease, including infants younger than three months of age.