NOTE: A surveillance case definition is a set of uniform criteria used to define a disease for public health surveillance. Surveillance case definitions enable public health officials to classify and count cases consistently across reporting jurisdictions. Surveillance case definitions are not intended to be used by healthcare providers for making a clinical diagnosis or determining how to meet an individual patient’s health needs.
An acute febrile illness characterized by frontal headache, retro-ocular pain, muscle and joint pain, and rash. The disease is transmitted by the Aedes aegypti mosquito and is confined to the tropics. Severe manifestations (dengue hemorrhagic fever and dengue shock syndrome) are rare, but may be fatal.
Laboratory Criteria for Diagnosis
- Isolation of dengue virus from serum and/or autopsy tissue samples, OR
- Demonstration of a fourfold or greater rise or fall in reciprocal IgG or IgM antibody titers in paired serum samples to one or more dengue virus antigens, OR
- Demonstration of dengue virus antigen in autopsy tissue samples by immunofluorescence or by hybridization probe
A clinically compatible illness with supportive serology (a reciprocal Immunoglobulin G (IgG) antibody titer of greater than or equal to 1280 or a positive Immunoglobulin M (IgM) antibody test on a single convalescent-phase serum specimen to one or more dengue virus antigens)
A case that is laboratory confirmed
Dengue hemorrhagic fever is defined as acute onset of fever with nonspecific symptoms. This is followed by hemorrhagic manifestations that may include a positive tourniquet test* and/or minor or major bleeding phenomena, thrombocytopenia (less than or equal to 100,000/mm3), and hemoconcentration (hematocrit increased by greater than or equal to 20%), or other objective evidence of increasing capillary permeability; or decreasing hematocrit after severe frank hemorrhage, such as upper gastrointestinal bleeding.
The definition for dengue shock syndrome follows all of the above criteria for dengue hemorrhagic fever and also includes hypotension or narrow pulse pressure (less than 20 mm Hg).
*Standard method (Wintrobe, 1967) utilizes a blood-pressure cuff to impede venous flow. A test is considered positive if there are equal to or greater than 20 petechiae/sq. in.