The PCR test converts the viral RNA into DNA and then, over multiple cycles (CTs) – makes copies of the DNA (amplification/replication), till there’s a detectable amount of virus.
The Cycle Threshold (CT) at which NZ considers a test positive for COVID is 40.MOH letter attached, under OIA.
The more cycles needed to detect the virus, the lesser the viral load . The World Health organization in Jan, warned against false positives, saying ” as disease prevalence decreases, the risk of false positive increases”.
This study at IHU-Méditerranée Infection, examined 3790 positive samples with known CT values to see whether they had viable virus, indicating the patients were infectious. It found that 70% of samples with CT values of 25 or less could be cultured, compared with less than 3% of those with CT values above 35.
So, how truly infectious are those who are locked down due to testing positive at the NZ cycle threshold of 40?
As seen , towards the right of the graph, at cycle threshold 35, there’s virtually no viral load . The authors state that cycles over 35 should NOT AFFECT public health measures.
Here, we declare a positive PCR test to be 40 cycles. Why do we need so many cycles of amplifications to detect the virus ? Simply because there was very little viral load. So, our positives at 40 cycles are of no concern as they have little/no viral load to transmit.
Weird. Yet, here we are – in a lockdown.
Correlation Between 3790 Quantitative Polymerase Chain Reaction–Positives Samples and Positive Cell Cultures, Including 1941 Severe Acute Respiratory Syndrome Coronavirus 2 Isolates
Column Author: Jaspreet Boporai. a 42 year old wife, mum of two kids (6, 4) and a dairy farmer. She and her husband manage 1500 cows over two farms in Western Southland for a large equity partnership.
Jaspreet got her degree in accounting from Massey and has also been bookkeeping for the last decade.
She and her husband moved to NZ in 2009, swapping 80 hour weeks in corporate banking for prob longer weeks in farming! (her husband has done his MBA and Jaspreet was a mortgage underwriter in India).
Hailing from Punjab (the epicentre of Indian farmer protests), India’s wheat basket, the love of land runs strong in the couple and wanting to go large scale farming got them to New Zealand.
Jaspreet’s family has been serving in the Indian army for many generations and nearly 30 years ago, her dad served in the Indian army contingent under the aegis of the United Nations in Africa. Thus, began her interest in all things UN related!