Listeria is a type of bacteria that can cause food poisoning. Listeriosis symptoms include diarrhea, nausea and fever. Pregnant women are 20 times more likely than other healthy adults to get listeriosis. Listeria infection is treated with antibiotics.
Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
Mary D. Nettleman, MD, MS, MACP is the Chair of the Department of Medicine at Michigan State University. She is a graduate of Vanderbilt Medical School, and completed her residency in Internal Medicine and a fellowship in Infectious Diseases at Indiana University.
Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
Listeriosis is a
disease caused by a gram-positive bacterium named Listeria that can penetrate
and replicate inside human cells.
Most people who are infected have few or no
symptoms; when symptoms are present, they usually consist of
aches, nausea, or
diarrhea. Some people may develop more severe symptoms such as
mental changes, brain abscesses, or death.
Although most people
have self-limited disease, people with risk factors such as an altered or
depressed immune response (for example,
pregnant females and their fetus or newborn,
AIDS patients) are at higher risk for getting the
disease and some are more likely to have more severe disease.
usually diagnosed by discovering that a person was associated with an outbreak
of Listeria-contaminated food or fluid or identified as a person associated
with the source of a known listeriosis outbreak. Definitive diagnosis is done
when Listeria bacteria are isolated from the patient's blood, cerebrospinal
fluid, or other body fluid.
Most normal people spontaneously clear the
infection and require no treatment. In contrast, people with risk factors should
be treated quickly with IV antibiotics.
People are exposed to Listeria
bacteria if they ingest contaminated food or fluid. Foods that are not cooked or
fluids that are not treated or pasteurized are frequently the sources of
infection. Pregnant females can transmit Listeria organisms to their fetus or to
Cooking foods, treating or pasteurizing fluids, and avoiding
food and fluids that may be contaminated with animal or human waste may prevent
The prognosis for most Listeria infections is excellent even if
people have consumed contaminated foods or fluid; however, the prognosis rapidly
declines in patients with risk factors if they are not quickly diagnosed and
U.S. government agencies are responsible for maintaining safe foods and
fluids for the U.S. population and may enforce regulations to ensure contaminated
products are reported, removed, recalled, and production and sales stopped until
processing meets acceptable standards of safety.
Reviewed by Mary D. Nettleman, MD, MS, MACP on 2/23/2012