Authors: Martha Powell, Future Science Group
A rapid and sensitive new low-cost test could detect Zika virus in mosquitoes and bodily fluids in addition to distinguishing between African and Asian strains of the virus, according to new research. This could allow more effective tracking of the disease and better targeting of control and prevention efforts.
In the study, published recently in Science Translational Medicine, researchers from Colorado State University (CO, USA) modified an existing technology, termed loop-mediated isothermal amplification (LAMP), to test for Zika.
The team demonstrated that the novel test could quickly detect Zika virus RNA in a range of samples including cultured infected cells, mosquitoes, virus-spiked human samples and infected patient serum, plasma and semen.
The advantage of LAMP is that it allows direct detection of Zika virus RNA without the need for RNA isolation or reverse transcription. This also makes it far less expensive, for example, a heat block for LAMP costs approximately US$250; in comparison, real-time PCR machines can cost US$15,000–$25,000.
Author Nunya Chotiwan (Colorado State University) commented: “Using LAMP to detect Zika virus would be much less expensive for developing countries. The majority of the countries involved in the current outbreak are not rich. It’s important for us to try to develop low-cost surveillance methods that might one day be used in these countries.”
The team demonstrated the test can indicate whether Zika is present in mosquito populations, and hope this could be utilized in the future to inform decisions about spraying and other disease-prevention methods.
The team state the next steps will include hospital-based tests; they plan to assess LAMP alongside current tests and also compare LAMP with PCR in mosquito and wildlife virus samples.
However, more work will be needed before this test can be utilized as a diagnostic tool. Lead Author Joel Rovnak (Colorado State University) concluded: “The human diagnostic side of things presents a much more significant challenge. It’s going to take a lot of time and a lot of data before people will allow regulatory agencies to OK LAMP as a bonafide test for a person that’s sick in the hospital.”
Sources: Chotiwan N, Brewster CD, Magalhaes T et al. Rapid and specific detection of Asian- and African-lineage Zika viruses. Sci. Trans. Med. 9 (338), eaag0538 (2017); http://source.colostate.edu/research-team-advances-low-cost-low-tech-zika-virus-surveillance-tool/