Saliva testing and molecular PPE - this week's top COVID-19 science stories

Scientists have developed a quick, cheap and painless saliva test to address the growing demand for extensive testing as lockdowns lift.

The test, spearheaded by scientists at the Yale School of Public Health, works by detecting the RNA – a molecular “photocopy” of DNA – of the new coronavirus in spit samples.

The hope is that the saliva test could be used alongside, or instead of, nose and throat swabs currently used to diagnose people with COVID-19.

Compared to the gold-standard nose and throat swab, the saliva test is less invasive, does not need to be conducted by a trained professional and skips the time-consuming and expensive step of extracting the nucleic acid from samples before testing. The scientists behind the test hope that these factors will increase testing compliance, protect healthcare workers from potential exposure to sick patients, avoid the problem of swab shortages and lower the cost per test.

Validation experiments reported in a paper published online (that has not yet been peer-reviewed) showed that the saliva test was sensitive and had a 94% match with the testing outcomes of nose and throat swabs.

The researchers estimate a cost per test of US$1.29–$4.37 and have requested that the United States Food and Drug Administration (FDA) authorize it for emergency use.

Scientists have urged caution at the approval of a vaccine in Russia after less than two months of testing in humans.

The announcement on Tuesday was made by President Vladimir Putin, who said the vaccine had passed all the required checks and his daughter had already been given it.

The Russian vaccine uses adapted strains of the adenovirus, a virus that usually causes the common cold, to trigger an immune response.

The methodology and results of the phase I and II clinical trials involving 76 people have yet to be released, peer-reviewed or published. Scientists warn that rolling out a vaccine that has not been tested for safety and efficacy on thousands of people (phase III testing), could endager the people who receive it.

Inspired by a unique kind of infection-fighting antibody found in llamas, camels and related animals, scientists at the University of California San Francisco have synthesized a molecule that they say is among the most potent anti-coronavirus compounds tested in a lab to date.

Called nanobodies because they are about a quarter of the size of antibodies found in people and most other animals, these synthetic molecules disrupt the machinery SARS-CoV-2 uses to attach to and infect cells.

In an aerosol formulation that the researchers tested (results published online, but not yet peer-reviewed), these molecules could be self-administered with a nasal spray or inhaler. The researchers hope that used once a day, they might be able to provide powerful, reliable protection against SARS-CoV-2 until a vaccine becomes available.

The research team hopes to ramp up manufacturing and clinical testing to see if the compound could provide viable protection against COVID-19.