The Puerto Rico Public Health Trust (PRPHT), a program of the Puerto Rico Science, Technology and Research Trust (PRSTRT), informed that CorePlus, one of the laboratories from the Clinical Laboratory Consortium Working Group for COVID-19 has a collection method using saliva to detect COVID-19. This technique is innovative in the island and the results of the COVID-19 PCR test are available in 24 hours.
“The validations of the tests arrived just in time for back to school and will be used to perform periodic tests and a faster detection of SARS-CoV-2 virus in students, teachers and school’s personnel to avoid outbreaks in schools,” said Dr. José F. Rodríguez Orengo, executive director of the PRPHT. “We are confident that now with these tests the reinstatement process will be much more efficient and bearable for everyone."
For the traditional collection method, a long swab is inserted into the nostril all the way to the back of the throat to obtain fluid from the nasopharynx. This same process is repeated in the second nostril. In contrast, saliva is a sample that is easily and naturally obtained anywhere. The procedure only requires the saliva to be deposited in a sterile vial to be processed in the laboratory.
"The availability of this test offers an additional alternative to continue making the diagnosis of the SARS-CoV-2 virus," said Mariano de Socarraz, CEO of CorePlus. "For its convenience, the saliva method is an ideal tool to use with students and the school community when they return to their presential classes." De Socarraz said CorePlus is committed to "make it easier to return to school after this long period of isolation and to make sampling a better experience."
To verify the effectiveness of the saliva collection method, CorePlus performed a comparative validation of both collection methods. The saliva method demonstrated an accuracy of 98%.
Despite the reduction in molecular testing on the island, the Clinical Laboratory Consortium Working Group of COVID-19, composed by Borinquen Laboratories, Immuno Reference Laboratories, Ponce Health Sciences University, Toledo Laboratories and CorePlus Laboratories; indicate that clinical laboratories have the capacity to process over 150,000 samples per month using the nasopharynx method. While it is expected to be able to process up to 10,000 additional tests monthly with the saliva method.
It should be noted, that at the moment the reference laboratories have exceeded the amount of 1.6 million molecular tests in Puerto Rico; and between molecular and antigens, 2 million tests have been passed on the island.
Benefits of the Saliva PCR Method
• The collection method offers a simple, fast, cost-effective and convenient opportunity.
• Reduces the risk of exposure for health professionals.
• Uses PCR technology which is still the most accurate process for detecting SARS-CoV-2.
• It can be used with the pooling methodology that allows multiple samples to be run in one well. Currently, this methodology is used with nasopharynx samples in the CorePlus laboratory.
The scientist highlighted that this test shows the evolution that Puerto Rico has had to handle the pandemic and recognizes the successes in the process, highlighting that we can be a model to follow for other jurisdictions. Even so, he was emphatic that the pandemic has not ended despite the fact that the positivity rate is at 3.6%, a result that has not been reflected since July 2020.
"This is not the time to lower our guard despite the fact that the data show an improvement," Rodríguez Orengo said, while urging people to continue practicing the so-called the Health Trilogy, which consists wearing masks covering the mouth and nose, washing hands with soap for at least 20 seconds and physical distancing.