Salmonellosis

*Salmonellosis (gastroenteritis)
*Typhoid Fever

appears black on plate

*Salmonella enterica and bongori

S. typhimurium
S. enteritidis

*S. typhi (CT 18 or Ty2)
*S. paratyphi

Type 3 secretion system, inserts itself, is not digested by lyzosome

*gram negative motile rod
*fimbria attatchment to epitheila
*intracellular parasite
*Type 3 secretion system
*H2S production (black on HEA plate)

*2500+ types

invasins

humans

digestive tract

oral route, ingestion of contaminated foods (eggs) and water

12-48 hrs

*bacteria attatches to the surface of small intestine, invades epithelial and immune cells.
*certain strains produce enterotoxins

*dysentery
*hemolytic-uremic syndrome (shiga toxins)

*endocytosis
*mutliplication within vesicle (evades lyzosomes)
*lysis and escapes cell

*gastroenteritis
*fever
Diarrhea (loose, moderate volume, no blood)

resolves in 4-5 dys
carriage (4-5 weeks) carrying the organism but not manifesting the symptoms

*severe dehyration
*worsening of pre-existing conditions
*bacteremia
*localized infections
*chronic carrier state
*reactive arthritis

*headache
*weakness
*loss of appetite
*coated tongue
*cough
*abdominal pain
*diarrhea or constipation
*rashes

*S. typhi
*S. paratyphil

1-2 weeks

*prolonged high fever (103-104 F for 3-4 weeks)

*headache
*weakness
*loss of appetite
*coated tongue
*cough
*abdominal pain
*diarrhea or constipation
*rash (less than 5 % of cases)

*intestional hemorrhage (10% of cases)
*intestional perforation (3%)
*tissue necrosis
*tissue necrosis
*infection of other organ systems
*mortality

*10%

*pasteurization
*proper food handling and preparation
*proper sanitation
*typhoid vaccine

50-80% protection against S. typhi

*Oral attenuated vaccine (Ty21a) every 5 yrs
*Injected polysaccharide (Vi) every 2 yrs

*rehydration therapy
*antibiotics (typhoid fever)

*azithromycin
*cephalosporin
*fluroquinolone
*high dose of amoxicillin + probenecid (3 months) for chronic carriers