Christchurch GP’s claims slammed by experts
Claims by a Christchurch GP that the most commonly used Covid-19 test is unreliable have been slammed by experts.
Dr Sam Bailey, who appeared on TVNZ’s medical show The Check Up, claimed in a video posted in early September that the polymerase chain reaction (PCR) test was unreliable – contradicting Ministry of Health information.
‘‘It doesn’t test for the virus, it tests for a piece of genetic material that we don’t know the significance of,’’ Bailey says in the video.
Microbiologist Siouxie Wiles said in an article for The Spinoff that the claims were wrong and being peddled by people ‘‘pushing the idea that Covid-19 can’t be managed and we just need to learn to live with the virus’’.
The Ministry of Health website says it is the most reliable test for diagnosing Covid19 if taken during the first week of the illness. ‘‘The PCR test looks for specific genetic sequences that are only found in the
SARS-CoV-2 virus,’’ Wiles said. ‘‘That makes it very suitable as a screening tool as it has such a low false-positive rate – people are highly unlikely to test positive unless the virus is present in the sample.’’
Testing was a crucial part of the testtrace-isolate strategy for stopping transmission of the virus, which had been proven to be effective, she said.
She did not mention Bailey by name or link to the video as it was ‘‘chock full of false information’’.
‘‘What I will say is just because someone is medically qualified doesn’t necessarily mean they know anything about diagnostic testing and the intricacies of quantitative PCR.’’
Professor of Biostatistics Dr Thomas Lumley told Newshub the PCR test looked for genetic sequences only found in the Covid-19 virus, and had a very low false positive rate.
Bailey, who has 92,000 followers to her YouTube channel, also said in the video she would not be getting a Covid-19 vaccine when one became available. She incorrectly said Covid-19 was similar to influenza, and that the flu vaccine did not reduce deaths.
Bailey’s video was shared to the NZ Public Party Facebook page, where it was interacted with more than 5800 times. Bailey told Newshub she stood by her claims and had no association with the NZPP.