PCRs past coronavirus cases detection Oxford University study says - PCRs are so sensitive to the presence of SARS-Cov - 2 that they could be causing the diagnosis of positive cases in patients who have actually passed the disease, according to new research.
The study, conducted by members of the Centre for Evidence-Based Medicine (CEBM) at Oxford University, reveals that "false positives" could be given due to the use of PCR as a standard test to diagnose coronavirus, reports The Independent.
Researchers have analyzed how the diagnostic test works, the result of which is interpreted in terms of 'yes' or 'no' to confirm the presence of the virus, and have found that it is able to detect traces of the genetic material of the virus for a longer period than it is infectious.
PCRs past coronavirus cases detection Oxford University study
That is, the person may still have the virus in his system after passing the disease, but it is no longer contagious. In fact, it could even detect fragments of dead viruses.
One of the authors of the study, Professor Carl Heneghan of CEBM, writes in The Spectator that this could explain why the increase in cases being seen in several countries is not implying a higher number of revenues.
The results of the investigation confirm evidence found earlier. In April, South Korea was alarmed by reports that more than 260 people in the country had tested positive again for coronavirus weeks after recovering from the disease.
The country's infectious disease experts appeared to explain that PCRs do not distinguish whether the virus is active or what it has identified are just fragments of an already dead virus.
End of PCRs past coronavirus cases detection Oxford University study
Coronavirus patients may have a prolonged intestinal infection even after the virus has disappeared from the airways
Coronavirus patients could have a prolonged intestinal infection even after the virus has disappeared from the airways, according to the findings of a new study by the University of Hong Kong collected by Bloomberg.
Researchers say the virus can replicate and infect the digestive tract even if it is no longer present in the airways, which are the main route of entry.
In addition, the authors warn, the infection can be active even if patients do not have gastrointestinal symptoms such as vomiting or diarrhea.
The study analyzed stool samples from 15 patients and found that 3 of them maintained an active viral infection that lasted up to 6 weeks after diagnostic tests based on respiratory tract samples ruled out the presence of coronavirus.
The finding "highlights the importance of long-term surveillance of coronavirus and health and the threat of possible fecal-oral viral transmissions," says Siew Chien Ng, associate director of the University's Intestinal Microbiota Research Center, in a statement obtained by Bloomberg.
The authors argue for greater emphasis on stool analysis, where viral remains are known to remain almost from the beginning of the pandemic. The University offers since March offered free stool screening tests to travelers arriving at the airport and ensures that it is a more reliable technique.
Implementing this type of test could identify patients whose PCR results are negative, the authors say.