Rako Science today announced it has just completed an extended validation study which concludes that the COVID-19 PCR saliva test is as accurate as nasopharyngeal swab tests.
In April, Rako Science received 152 unique saliva/nasal swab samples from the United States and shared them with two New Zealand laboratories. The samples were both nasal swab and saliva samples taken at the same time from people suspected of having COVID-19.
“We achieved 100% concordance between the University of Illinois laboratory and the iGENZ laboratory in Auckland and Victoria University’s laboratory in Wellington. Together we demonstrated 98.7% concordance with nasal swab results,” Rako Science Director, Dr Stephen Grice said.
“The sensitivity of the Rako saliva test is 97.0% when compared to nasopharyngeal swabs as the reference or ‘gold standard’. You can invert the comparison and use Rako’s saliva test as the gold standard and you find that nasopharyngeal swabs have a sensitivity of 97.0%. This demonstrates Rako’s saliva test has equal sensitivity to nasopharyngeal swabs.
“The Rako Science saliva test is excellent for early detection of COVID-19 which is crucial in New Zealand where we have elimination and low prevalence,” Dr Grice said.
Results
Of the 152 samples, there were 33 positive nasal swab samples and 119 negative nasal swab samples, with saliva samples taken from each patient at the same time. The thirty-three positive samples included 28 nasopharyngeal swabs and 5 mid-turbinate swabs.