A rapid test for Zika virus is a key part in the management of the viral disease, which has been causing a high number of infections in South America. The first case, from the current outbreak, was reported in Brazil in April 2015. The new test is modelled on one already in use for dengue virus.
One problem with the disease is, for those who develop symptoms, the symptoms can appear similar to those of other related RNA viral diseases like dengue and chikungunya. The current in-use test method involves taking blood samples and testing whether the person shows antibodies against the virus. This requires the use of a sophisticated laboratory with the means to perform a polymerase chain reaction test. The time-to-result is a matter of days or even weeks.
The new test is rapid and specific
. To create the test, the research team embedded synthetic gene networks onto small discs of paper. The small paper discs can detect 24 different RNA sequences found in the Zika viral genome. When the target RNA sequence is detected, a series of interactions are initiated and these transform the color of the paper from yellow to purple. The color change is visible to the naked eye; however, to quantify the level of viral material, the researchers are developing an electronic reader device.
The test was developed by team led by the Massachusetts Institute of Technology. The research group had the aim of developing a test that was portable and which could be stored at room temperature. This is achieved by freeze-drying the required gene networks onto the paper discs.
Interviewed by Bioscience Technology
, lead researcher James Collins explains further the advantages of the method: “We have a system that could be widely distributed and used in the field with low cost and very few resources.”
So far the device has been tested on monkeys and the Zika virus detected rate has been shown to be excellent. Further efficacy tests are required before samples from human patients are assessed.
The new test is described in the journal Cell
. The research paper is titled “Rapid, low-cost detection of Zika virus using programmable biomolecular components.”