Pune, September 6, 2020: A new study by scientists reveal that the main test which is used for the testing of the novel Coronavirus might be picking up traces of the old virus from previous infections. This may be the reason why an extensive rise in COVID-19 cases is being reported everywhere.
The study by the scientists says that on an average, the person can stay infectious only for a week but are testing positive even after seven days. This is due to the test being extremely sensitive and thus, it is picking up traces of the virus from previous infections.
Professor Carl Heneghan, one of the authors from the study said that the COVID-19 tests should include cut-off points so that very small hints of the virus do not indicate a positive result. He also said that because the tests might be picking up on old traces, cases are showing a drastic rise.
What is the ‘virus culturing’ method?
The University of Oxford’s Centre for Evidence-Based Medicine took part in the recent study and analysed the evidence from 25 studies.
The positive virus specimens were collected and put in a petri dish to find out if they would grow further. This process is known as ‘virus culturing’. This process was carried out to analyse if the specimens had any active viruses which had the potential to grow further or it just has traces of the dead virus.
The study by the scientists says that there is no indication of how much active virus is present in the samples in the current method of testing.
In conclusion, by the current method of testing, a person with a good amount of virus and a recovered person with leftover traces of the virus from the previous infection when tested would yield the same result and that is positive.
According to Professor Heneghan, false cases or test results can only be stopped if scientists work on the cut-off point in the current testing method.