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Typhoid
Fever
For the most current updates about
typhoid fever, please visit
CDC Travellers' Health
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Clinical
Features |
Typhoid
fever has an insidious onset
characterized by fever, headache,
constipation, malaise, chills, and
myalgia with few clinical features
that reliably distinguish it from a
variety of other infectious diseases. Diarrhoea is uncommon, and vomiting is
not usually severe. Confusion,
delirium, intestinal perforation, and
death may occur in severe cases. The
etiologic agent may be recovered from
the bloodstream or bone marrow, and
occasionally from the stool or urine.
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Etiologic
Agent |
Salmonella
serogroup Typhi. |
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Incidence |
400 cases per year in
the United States, mostly among travellers. An estimated 16 million
cases of typhoid fever and 600,000
deaths occur worldwide. |
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Sequelae |
Without therapy, the
illness may last for 3 to 4 weeks and
death rates range between 12% and 30%.
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Transmission |
Contaminated
drinking water or food. Large
epidemics are most often related to
fecal contamination of water supplies
or street vended foods. A chronic
carrier state--excretion of the
organism for more than 1 year--occurs
in approximately 5% of infected
persons. |
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Risk
Groups |
Risk is
very low in U.S.; higher among
international travellers (i.e., 812
per 1 million travellers to India),
and highest among persons living in
poverty in the developing world. |
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Surveillance |
All
reported cases are laboratory-confirmed
in states or at CDC. |
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Trends |
Modest
decrease in cases since 1994,
possibly related to newly licensed
vaccines marketed to international travellers.
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Challenges |
Increasing
resistance to available antimicrobial
agents, including fluoroquinolones,
may foretell dramatic increases in
case-fatality rates. Epidemics and
high endemic disease rates have
occurred in the Central Asian
Republics, the Indian subcontinent,
and across Asia and the Pacific
Islands. Growing evidence of
previously unrecognised disease in
children <5 years. |
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Opportunities |
The role
of new and effective vaccines as
control measures for epidemics and as
tools for elimination remains to be
explored. |
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December 2001
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