Salmonella and Salmonellosis Maryanne E. Tocidlowski, DVM Houston Zoo, Inc

What is it? Family Enterobacteriaceae Gram negative, rod bacteria, motile (most) Newer classification: 2 Species: S. enterica, S. bongori S. enterica - subspecies I, II, IIIa, IIIIb, IV, VI By biochemical and antigenic reactions Subspecies II, IIIa, IIIIb, IV, VI and S. bongori usually isolated from cold blooded animals and environment Older classification: 3 Species: Cholerae-suis, typhi, enteritidis Based on serologic and biochemical reactions Many serotypes of S. enteritidis Serotyping – 3 antigen structures O (surface layer), H (flagella), V (capsule)

How does it work? Penetration of the bacteria into intestinal wall, produces a cytotoxin, marked inflammatory response with enterotoxins, then fluid feces

Who is affected? Anyone exposed – est 1.4 million cases annually, 400 deaths Impaired immune systems Children (< 5 yo) – 5x more likely to get infected Infants Elderly All animals

What are the signs or symptoms? Starts 12-72 hours after exposure Diarrhea Fever Abdominal cramping Can last 4-7 days Systemic infections Occasionally long term illness (Reiter’s syndrome)

Where do you get it from? Worldwide occurrence Different subspecies vary in their epidemiology Lives in the intestine of humans and animals Eating foods contaminated with salmonella Of animal origin Vegetables Fecal-oral route Estimated 6% of infections from contact with reptiles and amphibians

Diagnosis Culture on selective media Biochemical reactions Serotyping O antigen – outer layer of cell H antigen – filament portion of flagellum V antigen – capsular polysaccharide

Is there a treatment? Usually not treated, self limiting If systemic, can give antibiotics Supportive oral fluids

Prevention of Salmonellosis HANDWASHING !! No reptiles/young birds in households with babies or children Cook foods-No raw or undercooked eggs, poultry, meats, unpasteurized dairy products Wash produce Handwashing

Prevention part 2 Report cases to the local public health departments Send isolates to City/County/State labs Ban on selling small turtles (< 4 inches) Treatment of municipal water supplies Improvement in farm hygiene, slaughter plant practices, produce harvesting and packaging Education of food handlers Irradiation of meats

Websites www.cdc.gov www.pueblo.gsa.gov/rc/turtles.html www.textbookofbacteriology.net/salmonella.html

Thanks