Enhancing surveillance for Dengue fever in Florida

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

World Distribution of Aedes aegypti and Dengue - 1999

Areas infested with Aedes aegyptiAreas with Aedes aegypti and dengue epidemic activity CDC

Centers for Disease Controland Prevention

Symptoms

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

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

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

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

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

Information required with samples

• Person's name• Onset date• Symptoms• Travel history• Name of person to whom results

should be send• Contact telephone numbers