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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 faecal 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 unrecognized 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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