Pandemic & Public Health Literature

6.    PCR Testing and Asymptomatic Testing

Summary:
The cumulative evidence pertaining to the PCR test, including the recent lab alert by the CDC (CDC, 07/21/2021), in addition to our knowledge pertaining to infectious disease, does not support either the use of the PCR test as a reliable test or the concept of asymptomatic testing.

• Corman et al. (2020) – paper claims the RT-PCR protocol to be “validated”, as well as being a “robust diagnostic methodology for use in public-health laboratory settings”
  
  
• Borger et al. (2020) – addresses numerous issues pertaining to the Corman paper including:
  
  • Significant methodological issues pertaining to the
    • Probe (a fragment of DNA or RNA used to detect the presence of a specific DNA fragment within a sample) and Primer (short strand of DNA or RNA that serves as the starting point for DNA synthesis) design.
    • Reaction temperature,
    • Number of amplification cycles (Jaafar et al., 2020) –> At Ct=35, <3% of cultures are positive.
    • Biomolecular validation
    • Positive & negative controls to confirm/refute specific virus detection
    • Standard Operating Procedure (SOP) not available
    • Consequences of Errors mentioned in the first five points listed –> False positive results
      
      
  • Additional issues
    • Paper was not peer reviewed
    • Authors – members of the editorial board of the journal
      
      
• Cevik et al. (2021)
  
  • “No study detected live virus beyond day 9 of illness, despite persistently high viral loads.”
    
    
  • “Our study shows that despite evidence of prolonged SARS-CoV-2 RNA shedding in respiratory and stool samples, viable virus appears to be short-lived. Therefore, RNA detection cannot be used to infer infectiousness.”
    
    
• “Historically people need to realize that even if there is some asymptomatic transmission [of covid-19], in all the history of respiratory-borne viruses of any type, asymptomatic transmission has never been the driver of outbreaks. The driver of outbreaks is always a symptomatic person. Even if there’s a rare asymptomatic person that might transmit, an epidemic is not driven by asymptomatic carriers” (Fauci, 2020) (https://www.youtube.com/watch?v=w6koHkBCoNQ&feature=youtu.be&t=2642)
  
  
• “We found some evidence that SARS-CoV-2 infection in contacts of people with asymptomatic infection is less likely than in contacts of people with symptomatic infection (relative risk 0.35, 95% CI 0.10–1.27).” (Buitrago-Garcia et al., 2020)
  
  
• “Unusually in disease management, a positive test result is the sole criterion for a covid-19 case. Normally, a test is a support for clinical diagnosis, not a substitute….. It’s also unclear to what extent people with no symptoms transmit SARS-CoV-2. The only test for live virus is viral culture. PCR and lateral flow tests do not distinguish live virus. No test of infection or infectiousness is currently available for routine use. As things stand, a person who tests positive with any kind of test may or may not have an active infection with live virus, and may or may not be infectious….., no study was able to culture live virus from symptomatic participants after the ninth day of illness, despite persistently high viral loads in quantitative PCR diagnostic tests.” (Pollock and Lancaster, 2020)