SARS-CoV-2 Environmental Surface Testing using RT-PCR
HP Environmental now offers lab-based testing for the presence of SARS-CoV-2, the virus responsible for COVID-19. Testing for the presence of SARS-CoV-2 viral RNA on environmental surfaces is the most direct and definitive test for ensuring effective disinfection procedures. The COVID-19 virus analysis is based on the CDC's 'Real-Time RT-PCR Panel for Detection' and adapted and validated for environmental samples. In critical, high-risk scenarios, and for targeted testing of areas of known contamination, appropriately validated RT-PCR methods can provide the highest level of confidence for businesses and workplaces looking to return to work while ensuring employee safety and health.
What is RT-PCR testing for SARS-CoV-2?
Reverse transcription polymerase chain reaction (or RT-PCR) is a technique used to measure RNA. The technique works by converting RNA into its complementary DNA (cDNA) strands using a transcriptase enzyme that is then amplified using the polymerase chain reaction. The amplified cDNA is measured using fluorescent compounds added to the mixture that bind to the cDNA. Specific primers and probes are also added to the mixture that are unique to the COVID-19 virus that ensure that only RNA from the COVID-19 virus is detected.
Why use RT-PCR testing?
The RT-PCR Test is used to examine surfaces for the presence of SARS-CoV-2 RNA. Studies have shown that under certain conditions SARS-CoV-2 can reside for a period of time on surfaces outside the human body. Scientists have reported that the virus can remain active on plastic and stainless steel surfaces for up to 2 to 3 days and for up to 24 hours on cardboard. These findings suggest that individuals may acquire SARS-CoV-2 after touching a contaminated surface or object with the virus on it and then touching your eyes, nose or mouth. While the COVID-19 virus is easily killed using soap and water or an EPA-approved disinfectant, its presence on a surface following treatment is the most definitive test to validate the efficacy of a cleaning and disinfection protocol of high-touch surfaces to protect against infection from the COVID-19 virus.
What does the RT-PCR test report?
The test reports the presence/absence of RNA characteristic of SARS-CoV-2, which is the cause of COVID-19. The test measures the same gene targets (ORF1ab, N gene & S gene) as clinical tests used for COVID-19 testing in humans. Since this test is specific to SARS-CoV-2 and no other virus, it is the most direct, specific and sensitive test to detect the presence of COVID-19 virus RNA on a surface.
Can this test be used on humans?
No. While the test reports the presence/absence of SARS-CoV-2 RNA and measures the same gene targets as clinical tests used for COVID-19 testing in humans, this test is designed to detect the presence of the COVID-19 virus RNA on a physical surface such as desks, doorknobs, and other “high-touch” surfaces.
What does the RT-PCR test report?
For a COVID-19 virus to be infectious, its cell membrane and nucleocapsid (structural protein that encapsidates the viral RNA) must be intact. Unprotected viral RNA is unstable in the environment as RNA-degrading enzymes can destroy it rapidly. Therefore, a positive swab test of a surface would indicate the presence of the COVID-19 virus RNA in a stable, hence potentially infectious form.