When We Can Stop Pre-Procedure Screening For COVID-19

Briefly noted: S Sultan, SM Siddique et al. Gastroenterol 2020; 159: 1935-1948. Full text: AGA Institute Rapid Review and Recommendations on the Role of Pre-Procedure SARS-CoV-2 Testing and Endoscopy

Table 1 provides a summary of the recommendations and indicates a threshold for which routine pre-procedure testing may not be needed:

  • “For endoscopy centers where the prevalence of asymptomatic SARS-CoV-2 infection is low (<0.5%), the AGA suggests against implementing a pretesting strategy.”
  • Conditional recommendation, very low certainty evidence
  • Rationale: “In low-prevalence settings, a pretesting strategy may not be informative for triage due to the high number of false positives, thus PPE availability may drive decision-making.”

My take: Particularly after the rollout of vaccination to health care providers, routine testing for SARS-CoV-2 is not likely to be needed once the prevalence drops to low levels.

Related blog posts:

COVID-19 -New Infection Fatality Data & How to Fix the Testing Mess

From Annals of Internal Medicine 2020 https://doi.org/10.7326/M20-5352: J Blackburn et al. Full Text: Infection Fatality Ratios for COVID-19 Among Noninstitutionalized Persons 12 and Older: Results of a Random-Sample Prevalence Study

Background: Mortality rates have been calculated from confirmed cases, which overestimates the infection fatality ratio (IFR). To calculate a true IFR, population prevalence data are needed from large geographic areas where reliable death data also exist.

Results: The Table below suggests IFR of 0.01% for those <40, 0.12% for those 40-59, and 1.71% for those ≥60 in noninstitutionalized persons.  The Table indicates nearly a 3-fold increase risk in Non-White persons. Whites had an IFR of 0.18%; non-Whites had an IFR of 0.59%. Also, I think the Table incorrectly suggests that Females have a higher IFR than Males (but the numbers suggest that they are equivalent).

From The New Yorker, Atul Gawande: We Can Solve the Coronavirus-Test Mess Now—If We Want To

This is a lengthy article which describes some of the mistakes that we’ve made with testing, some of the technical details with various tests, pooled testing, at-home testing, wastewater testing, and how to fix testing (including assurance testing) to gain control of this pandemic.

An excerpt:

We could have the testing capacity we need within weeks. The reason we don’t is not simply that our national leadership is unfit but also that our health-care system is dysfunctional….

In the United States, getting a test is anything but easy…[And] through early August, results routinely took four days or more, making the tests essentially useless. 

Assurance testing” has been required by countries such as IcelandFrance, and Germany for travellers from abroad in order to avoid a mandatory two-week quarantine