Transcript Shigellosis

Shigellosis
Bacterial dysentery
Microbial Agent
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Four species of Shigella:
– boydii
– dysenteriae (causes deadly
epidemics)
– flexneri (1/3 of U.S.)
– sonnei (about 2/3 of U.S.)
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448,240 cases in U.S. last
year for sonnei and flexneri.
dysenteriae occurs mostly in
Africa and Central America
Case fatality rates of 5-15%.
Signs and Symptoms
• Infectious disease causing
diarrhea (bloody), fever, and
stomach cramps
• Usually resolves in 5-7 days.
• Children and elderly may
have diarrhea so severe they
need to be hospitalized.
• A severe infection in a child
less than 2 may have
seizures.
• Some show no signs at all,
but still pass the Shigella
bacteria to others.
Diagnosis
• Many diseases cause
the same symptoms
• Determining that
Shigella is the cause
of the illness depends
on laboratory
• Tests identify if it is
Shigella, and what
type
• Stools of an infected
person are tested
Diarrhea with blood and mucus is
a typical symptom of Shigella.
Treatment and Prevention
• Can usually be treated
with antibiotics
• There is no vaccine to
prevent shigellosis
• Frequent hand washing
can help
• Food safety and regular
drinking water treatment
is best prevention
Vegetables could be contaminated by crops
harvested from a field with sewage, flies
bred in infected feces, and food handlers
that are not properly washing their hands