Dengue rapid testing
As dengue is a recurring problem in many Pacific Island countries and territories (PICTs), it is essential that diagnostic laboratory testing is available for good patient clinical management and also for guiding appropriate public health activities to contain and prevent outbreaks.
Current laboratory testing is based on two main types of assay: detection of IgG and IgM antibodies by ELISA, and detection of virus by PCR. With the ELISA methods, there are a number of commercial products available that utilise a traditional microplate EIA system as well as a rapid diagnostic EIA system. In most PICTs, which have limited resources in technical performance abilities, the rapid diagnostic test has become a valuable tool for dengue testing.
The most well-known rapid diagnostic test for dengue in the region is the Panbio Duo rapid strip test. PPHSN, through LabNet, has been recommending that PICTs utilise this test as an initial screening test and then to send specimens with positive results to a referral lab for confirmation either by a second ELISA method or by PCR. Recently, some additional rapid diagnostic tests that have great potential for routine screening use have been introduced to the market. The two most notable new products are the Pentax IgG/IgM particle agglutination test and the Bio-Rad NS1 antigen strip test. Test validations are being conducted on these assays to evaluate their performance in reliable diagnosis of dengue disease.
With the availability of various testing products, it is essential that all applicable factors be considered before selecting a product for consistent use. PPHSN–LabNet is working closely with its technical partners, primarily Institut Pasteur and Queensland Health Scientific Services, to evaluate these test kits so as to make appropriate recommendations to PICTs on the best kit to use. PPHSN–LabNet will continue to evaluate test kits on a regular basis to ensure that technical parameters are maintained and also as a mechanism to explore new and improved test methods.