- The intestinal tract in humans
- Human or animal feces containing
Salmonella; transmitted by the fecal-oral route. Since many different
animals carry Salmonella in their intestinal tract, people usually
become infected from ingesting improperly refrigerated, uncooked or undercooked
poultry, eggs, meat, or dairy products contaminated with animal feces.
- Around 50,000 cases of salmonellosis
are reported annually in the U.S. but most cases go unreported. An estimated
2,000,000 - 3,000,000 people a year in the U.S. become infected with Salmonella
and at least 500 die.
- The majority of Salmonella
cause diarrhea, but one species, S. typhi, frequently disseminates
into the blood and causes a severe form of salmonellosis called typhoid fever.
In 1998, 375 cases of typhoid fever were reported in the U.S. but most of
these cases were acquired during foreign travel
is the most common form of salmonellosis. Symptoms generally appear 6-48 hours
after ingestion of the bacteria and include vomiting, nausea, nonbloody diarrhea,
fever, abdominal cramps, myalgias (def),
and headache. Symptoms generally last from 2 days to 1 week followed by spontaneous
- All species of Salmonella
can cause bacteremia (def)
but S. typhi, S. paratyphi, and S. choleraesuis are the
most common species to cause bacteremia.
by Michael Zapor, MD, PhD, Fellow, Infectious Disease Section, Department of
Medicine, Walter Reed Army Medical Center and
David P Dooley, MD, Chief, Associate Fellowship Director, Department of Medicine,
Infectious Disease Service, Brooke Army Medical Center; Associate Professor,
Department of Medicine, University of Texas at San Antonio.