Researchers from New York University (NYU), US, are developing a test for Zika virus that uses saliva to identify diagnostic markers of the virus faster than current tests.
The new Zika virus test was adapted from an existing model developed by NYU and its New York based collaborator Rheonix, Inc for rapid HIV testing.
Population concentration and global air travel are factors in the growing frequency in outbreaks of infectious diseases. In 2015, an outbreak of Zika virus in Brazil spread to other countries in central and south America, the Caribbean and the Southern United States.
This resulted in the World Health Organization (WHO) declaring Zika and its link to birth defects a public health emergency.
Maite Sabalza , PhD, a postdoctoral associate at the Department of Basic Science and Craniofacial Biology at NYU Dentistry, said: “The recent Zika virus outbreak confirms that we need an effective surveillance and diagnostic program to reduce the impact of future emerging infectious diseases,”
It is critical to combat the spread of infectious diseases by identifying pathogens early. Testing often involves two separate steps:
- One to detect a pathogen’s nucleic acids (RNA or DNA); and
- One to test for antibodies, the proteins the body produces in response to pathogens.
Usually to test for Zika virus, blood samples are often used and processed using a common diagnostic technique known as real-time polymerase chain reaction.
However, blood may not be the best fluid to test, as the virus stays longer in saliva, semen and urine. In addition, antibodies can remain for months or years in those bodily fluids, which is why it’s essential for diagnosis to also detect antibodies after infection.
How will the test improve matters?
The benefits of the saliva test are that it is non-invasive, cost effective and easier to collect than blood or urine. It also has the potential to produce results in a matter of minutes instead of hours or days.
Current tests take nearly three hours, while specific antibody tests can take several weeks.
NYU researchers are using a different method called isothermal amplification, which can detect a virus’ nucleic acids in as little as 20 minutes, and antibody tests that can take less than an hour using Zika specific antigens.
Study author Daniel Malamud, PhD, professor of basic science at NYU Dentistry, said: “The sooner you can identify a pathogen, the sooner steps can be taken to treat and isolate people. During an epidemic, you could test people before they get on a plane.
“The future of going through security at the airport may not be taking off your shoes, but instead spitting into a tube.”
The research appeared in PLOS ONE and the Journal of Visualized Experiments.