Saliva COVID-19 Test Kits

20 Oct 2020 | Uncategorized

A Singapore-based medical company has devised a quicker, less invasive test for detecting the COVID-19 coronavirus.

Veredus Laboratories launched two new test kits on Thursday (Sept 17). The test can reduce the time taken to determine is a person has COVID-19 by up to 40 minutes.

One of the kits is used with nasal swab samples and has been on sale here since June ahead of its official launch. The other uses saliva, which is less invasive to procure from patients.

Speaking to reporters on Thursday, Dr Rosemary Tan, the company’s chief executive officer, explained that regular Covid-19 tests involving a laboratory technique called polymerase chain reaction (PCR) tests can take up to two hours.

In this process, a nasal swab is taken from a patient by sticking a swab up his or her nose. The swab samples are then placed in a virus medium where it is sent to a laboratory. There, ribonucleic acid (RNA), which stores the genetic information of the virus, is extracted and then put through a PCR test to identify the presence of the Sars-CoV-2 coronavirus.

“When you are doing a test, you take longer and you need more manpower and have more exposure (to the virus),” Dr Tan said.

However, her company has developed a buffer solution that eliminates the need for the extraction process, shaving the time required for the PCR test by up to 40 minutes, Dr Tan said.

The saliva or swab samples are mixed with the buffer, which can then be put immediately through a PCR test. Through this process, the coronavirus can be detected within half an hour, or one-and-a-half hours at most.

Dr Tan declined to disclose the chemicals in the buffer solution, saying there are proprietary rights.

The test kit for nasal swabs, known as ZeroPrep Swab Buffer Kit, has been sold in Singapore and overseas since June this year, while the ZeroPrep Saliva Collection Kit is pending approval from the Health Sciences Authority here.

If approved, the latter will be the first saliva-based test kit in Singapore that does not require the extraction process, Dr Tan said. It is also the first few kits of this type available worldwide, she added.

She declined to disclose her markets and sale numbers for the ZeroPrep Swab Buffer Kit, but said that the company is able to produce one million of each type of test kit a week.

The Ministry of Health said in June that it was studying the feasibility of incorporating saliva-based tests into its testing regime.

One key advantage of the saliva-based test kit is that those in quarantine can test themselves, reducing the risk of the virus spreading to others, Dr Tan said.

She admitted though, that using saliva samples could compromise the sensitivity of the test since they have lower viral loads compared to swab samples.

However, users are required to produce at least 1ml, equivalent to a quarter teaspoon, of saliva sample to ensure that there is enough viral load to be detected by a PCR test. This is enough to even detect the virus in asymptomatic patients, Dr Tan said.

Veredus Laboratories is working with its parent company, Sekisui Chemical, a Japanese plastics manufacturer, to market the test kits in Japan.

By Navene Elangovan