Enhancing surveillance for Dengue fever in Florida

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Enhancing surveillance for Dengue fever in Florida

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Dengue fever

• Mosquito-borne viral disease
• 4 serotypes (DEN 1,2,3,4)
• Infection with one serotype confers immunity only
  to that serotype
• Subsequent infection with another serotype
  increases risk of severe disease (dengue
  hemorrhagic fever/shock syndrome)
• severe disease most common in children

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World Distribution of Aedes aegypti and Dengue -
1999
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Symptoms

• Fever with 2 or more of
• headache
• eye pain
• muscle pain
• joint pain
• rash
• hemorrhagic symptoms

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Why we care about dengue in Florida

• Last epidemic 1934-35
• 15,000 cases in Miami (135,000 pop)
• Indigenous transmission occurred in Texas in 1986
  and 1995
• The mosquito that transmits dengue is abundant in
  Florida
• Dengue is endemic in Cuba, Mexico, and elsewhere
  in Caribbean, central and South America

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Enhanced dengue surveillance showed we have more
cases than we thought

• 1987-96 mean of 1.3 cases per year reported in
  Florida
• 1997-98 enhanced laboratory surveillance found
  18 cases
• All imported
• Demonstrates potential for introduction of
  infection
• We have the makings for endemic dengue in Florida

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Increasing surveillance in Florida

• Tampa branch laboratory offers FREE dengue
  testing
• Testing is more reliable than commercial labs
• Provides state with faster results
• Early detection earlier control efforts

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Requirements for testing

• Serum (at least 1/2 ml)
• Need acute and convalescent (3-4 weeks apart)
• If you have CSF, send it it can provide some
  additional information, but does not replace the
  two sera
• Lab performs IgM and IgG ELISA tests

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Information required with samples

• Person's name
• Onset date
• Symptoms
• Travel history
• Name of person to whom results should be send
• Contact telephone numbers