A number of commercial rapid format serological test-kits for anti-dengue IgM and IgG antibodies
have become available in the past few years, some of these producing results within 15 minutes.70
Unfortunately, the accuracy of most of these tests is uncertain since they have not yet been properly
validated. Rapid tests can yield false positive results due to cross-reaction with other flaviviruses,
malaria parasite, leptospires and immune disorders such as rheumatoid and lupus. It is anticipated
that these test kits can be reformulated to make them more specific, thus making global laboratorybased
surveillance for DF/DHF an attainable goal in the near future. It is important to note that these
kits should not be used in the clinical setting to guide the management of DF/DHF cases because
many serum samples taken in the first five days after the onset of illness will not have detectable IgM
antibodies. The tests would thus give a false negative result. Reliance on such tests to guide clinical
management could, therefore, result in an increase in case-fatality rates.q
In an outbreak situation, if more than 50% of specimens test positive when rapid tests are used,
dengue virus is then highly suggestive of being the cause of febrile outbreak