Saliva Test to Detect Asymptotic COVID-19 Cases

One of the challenges in the COVID-19 pandemic has been creating a mass, efficient test and identifying asymptomatic cases. In an attempt to curb both these issues, scientists from Hokkaido University have developed a coronavirus screening technique that uses saliva, reported International Business Times .

What is the Test?

The test makes use of saliva to detect silent carriers of the coronavirus who show little to no symptoms of the disease. As a result, these individuals present a great threat of infecting huge number of people as they are unaware they are carriers.

“Rapid detection of asymptomatic infected individuals will be critical for preventing COVID-19 outbreaks within communities and hospitals.”

Takanori Teshima, lead author of the study and Professor and Chairman of Department of Hematology, Hokkaido University in Japan.

How Does it Work?

To conduct this test, saliva and nasopharyngeal swabs of individuals with no coronavirus symptoms are compared and subjected to two diverse virus amplification tests.

This is widely known Polymerase chain reaction (PCR) test and the recondite Reverse Transcription Loop-mediated Isothermal Amplification (RT-LAMP) test.

What is the Efficacy Of The Test?

For the study, the said team compared saliva samples of 2000 asymptomatic individuals. Nasopharyngeal swabs detected the virus in 77-93 per cent of the subjects, while saliva samples helped in the identification of the disease in 83-97 per cent of the subjects

In over 99.9 per cent of the subjects, both the tests were efficient in identifying those without the disease. The viral load discerned in the saliva and nasopharyngeal swabs were highly correlated and equivalent. The PCR sensitivity is much higher than the 70 per cent that came from the initial data of symptomatic cases, observed the study authors.

The advantage of using saliva testing is that it not only reduces the discomfort caused to the examinees, it also reduces the chances of contact with examiners and their exposure to COVID-19.

However, it is to be noted that the team did not follow up on the clinical outcomes of the sample providers.

(With inputs from International Business Times )