Soon, 'rapid 20 min saliva test' to sniff out dengue

According to a new research, detecting dengue may soon be as easy as spitting into a made-in-Singapore rapid test kit.

The Institute of Bioengineering and Nanotechnology (IBN) of A*STAR has developed a paper-based disposable device that will allow dengue-specific antibodies to be detected easily from saliva within 20 minutes. This device is currently undergoing further development for commercialization.

IBN Executive Director Jackie Y. Ying shared their rapid diagnostic kit can detect a key dengue antibody from saliva that is present in early-stage secondary infection and the ability to differentiate between primary and secondary dengue infections makes it a valuable early diagnosis tool that would help to ensure timely treatment and proper care of patients.

Patients with secondary infection, who have previously been infected with other serotypes of dengue virus, stand a higher risk of developing dengue hemorrhagic fever or dengue shock syndrome.

Currently, dengue infection is diagnosed in the laboratory by testing the patient's blood sample for the presence of dengue antigens or antibodies. IBN's device, on the other hand, is capable of detecting IgG, a dengue-specific antibody found at the onset of secondary infections, directly from saliva in one step.

Unlike blood samples, saliva can be collected easily and painlessly for rapid point-of-care diagnostics. However, unlike other body fluids, it cannot be applied directly to commercially available test kits as it would cause the sensor nanoparticles to stick haphazardly to the test strip. In addition, conventional paper-based tests are not designed to handle the larger sample volume of saliva required.

The kit can also be adapted to detect other infectious diseases such as HIV and Syphilis. The IBN researchers are also investigating the use of other common fluid samples, such as blood, urine and serum for rapid, high-sensitivity test kits.

The study is published in the journal Lab on a Chip.