Saliva Testing Reveals Super-carrier Risks On New Zealand Borders
Just 2% of COVID-19 positive cases carry 90% of the circulating SARS-CoV-2 virus in a population which means most people with COVID-19 don’t infect others but a few people are super-carriers who can infect many people, according to a Colorado University research study.
“We hope that the Sydney visitor to Wellington was not one these super-carriers even if infected with the more transmissible Delta variant,” Rako Chief Science Officer Dr Stephen Grice said.
“It is good news the visitor had a first vaccination shot as it is possible this reduced the risk of being a super-carrier which supports Chris Hipkins’ comment that it is a low risk but not no risk,” he said.
In 2020 Colorado University (CU), using the same saliva test as Rako Science in New Zealand, tested 72,500 students who reported no symptoms, and 1405 positive cases were identified and just 2% of those cases carried 90% of the circulating SARS-CoV-2 virus.
CU also compared its positive samples with samples from hospitalized COVID-19 patients and found that viral loads in asymptomatic people were "indistinguishable" from highly symptomatic people.
“Coming in contact with a super-carrier is a game of chance so you have to continue to be careful. And some asymptomatic people are carrying a viral load as high as someone with COVID-19 who is very sick in hospital,” Dr Grice said.
“If you do come into contact with a super-carrier there is much higher risk and there is no difference whether they are coughing or not,” he said.
Rako Science delivers surveillance testing at scale to protect New Zealand workers, business and vulnerable communities. Rako Science’s COVID-19 PCR saliva test is painless, non-invasive, repeatable and as accurate as nasopharyngeal swab tests.