salmonella

/sal'meuh nel"euh/, n., pl. salmonellae /-nel"ee/. Bacteriol.

any of several rod-shaped, facultatively anaerobic bacteria of the genus Salmonella, as S. typhosa, that may enter the digestive tract of humans and other mammals in contaminated food and cause abdominal pains and violent diarrhea.

[ < NL (1900), after Daniel E. Salmon (1850-1914), U.S. pathologist; see -ELLA]

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Any of the rod-shaped, gram-negative, non-oxygen-requiring bacteria that make up the genus Salmonella.

Their main habitat is the intestinal tract of humans and other animals. Some of the 2,200 species exist in animals without causing disease; others are serious pathogens. Any of a wide range of mild to serious infections caused by salmonellae are called salmonellosis, including typhoid and paratyphoid fever in humans. Refrigeration prevents their reproduction but does not kill them; as a result, many salmonellae can develop in foods, which, when eaten, can cause gastroenteritis. Chickens are major reservoirs of salmonella, and chicken and eggs are the principal source of human poisoning, whose symptoms include diarrhea, vomiting, chills, and painful headaches. Other food sources include unpasteurized milk, ground meat, and fish.

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▪ bacteria

      group of rod-shaped, gram-negative, facultatively anaerobic bacteria in the family Enterobacteriaceae. Their principal habitat is the intestinal tract of humans and other animals. Some species exist in animals without causing disease symptoms; others can result in any of a wide range of mild to serious infections termed salmonellosis in humans. Most human infections with Salmonella result from the ingestion of contaminated food or water.

 Salmonella typhi causes typhoid fever; paratyphoid fever is caused by S. paratyphi, S. schottmuelleri, and S. hirschfeldii, which are considered variants of S. enteritidis.

      Refrigeration prevents bacterial reproduction but does not kill these microorganisms. As a result, many Salmonella can develop in foods, which, when ingested, can result in gastroenteritis.

      S. choleraesuis, from swine, can cause severe blood poisoning in humans; S. gallinarum causes fowl typhoid; and S. arizonae has been isolated from reptiles in the southwestern United States.

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