On 21 December 2022, Cambridge University, published under the reference of 30 other studies, a study with its research conclusions with regard to the usefulness of PCR testing for Covid19 in asymptomatic individuals.
As a reminder, in all countries that participated in the play, several million people have been subjected to compulsory PCR testing and quarantine on one or even several occasions merely because they had had contact with an " infected " person, even though that contact showed no symptoms and neither did they themselves. All persons entering a hospital for any other condition, surgery or simple consultation were similarly required to undergo a PCR test. If they did not, they were sent away and not helped.
Cambridge arrives at the following findings :
The testing of asymptomatic patients for severe acute respiratory coronavirus virus 2 (SARS-CoV-2) (i.e. "asymptomatic screening") to try to reduce the risk of nosocomial transmission is extensive and resource-intensive, and it is not clear what the benefit of such testing is when added to other layers of infection-prevention controls. Moreover, the logistical challenges and costs raise questions about the usefulness of such infection prevention. in relation to the implementation of screening programmes, data showing the absence of significant aerosolisation during elective controlled intubation, extubation and other procedures, and the adverse effects of asymptomatic screening on patients and institutions Consequently, the Society for Healthcare Epidemiology of America (SHEA) advises against the routine universal use of asymptomatic screening for SARS-CoV-2 in healthcare facilities. In particular, asymptomatic pre-procedure screening is unlikely to provide additional benefit in preventing transmission of SARS-CoV-2 in the procedural and perioperative setting when other infection prevention strategies are employed, and it should not be considered a requirement for all patients.
"In conclusion, the application of asymptomatic screening is a unique but costly tool that is arguably overused. Prior to the implementation of a large-scale asymptomatic screening programme, strengthening existing layers of protection (e.g. moving to universal use of an N95 respirator when performing certain procedures on a patient, active versus passive screening of healthcare staff for signs of COVID-19, reducing the classification of higher-risk wards and improved ventilation) is a more practical and reasonable approach. Stepping up and reducing screening can be labour-intensive, such as activating and dismantling testing sites, purchasing testing supplies and reagents, redirecting staff to collect, process and test specimens, reconfiguring the test ordering process and training patients and staff. Institutional risk assessments combined with data indicating ongoing transmission of SARS-CoV-2 (despite strengthening existing control layers and assessing compliance with infection prevention measures) or particularly high-risk populations (e.g. social or behavioural care institutions, transplant wards) should determine whether asymptomatic screening should be added to institutional practices. While it is imperative to prevent healthcare-associated spread of respiratory pathogens, we need to critically assess interventions that, when added to the core layers of infection prevention yet do not have the intended effect and may have unintended consequences for patients and medical staff.
The PCR test was not useful over the whole line but that's another debate.