Current gold-standard tests to detect the virus require expensive lab equipment and trained personnel, researchers said.
Low-cost diagnostic methods have been reported but cannot detect low levels of the disease or do not distinguish between Zika and similar viruses such as dengue, they said.
Changchun Liu from University of Pennsylvania in the US and colleagues wanted to design a rapid, low-cost, and more reliable point-of-care detection test.
To ensure their system would be highly selective for Zika without confusing it with similar viruses, researchers looked for and found a stretch of genetic code that is nearly identical for 19 different strains of the Zika virus infecting people in the Americas but not in other pathogens.
If the Zika-specific genetic sequence is in a saliva sample, a dye within the system will turn blue within 40 minutes. The test even works if low levels of the sequence are present, researchers said.
The findings were published in the journal Analytical Chemistry.