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.
Albert Gurusamy
Laboratory Specialist
SPC
