Test sensitivity for infection versus infectiousness of SARS‐CoV‐2

Abstract

The most commonly used test for the presence of SARS‐CoV‐2 is a PCR test that is able to detect very low viral loads and inform on treatment decisions. Medical research has confirmed that many individuals might be infected with SARS‐CoV‐2 but not infectious. Knowing whether an individual is infectious is the critical piece of information for a decision to isolate an individual or not. This paper examines the value of different tests from an information‐theoretic approach and shows that applying treatment‐based approval standards for tests for infection will lower the value of those tests and likely causes decisions based on them to have too many false positives (i.e., individuals isolated who are not infectious). The conclusion is that test scoring be tailored to the decision being made.

Optimal allocation of scarce PCR tests during the COVID-19 pandemic

“…As a word of caution, the analysis implicitly assumes that the value of a positive PCR test is the same both for asymptomatic and symptomatic individuals. The value of a positive PCR test lies in reducing the transmission rate by isolating infectious individuals [12]. While the U.S. Centers for Disease Control and Prevention [13] considered infectiousness of asymptomatic individuals to be 25% lower relative to symptomatic patients (in the pre-Omicron era), asymptomatic individuals may transmit more than symptomatic individuals if they are unaware of their infection [14].…”

Examining the Relationship Between Workplace Industry and COVID-19 Infection

“…While the main interventions for limiting the spread of COVID-19 in the workplace include social distancing, housekeeping and sanitation, use of PPE, restricting site access, and ventilation, 5,44 RAS represents a promising approach for preventing asymptomatic infectious individuals from unwittingly transmitting the virus to their colleagues at work or to their families within the household 2,45 by offering an additional layer of protection alongside existing measures. 2,34,46 Moreover, coupled with a data system, it can provide broader surveillance of viral transmission and potentially inform on industry-or job-specific variation in the implementation of other measures. 47 In light of this, the Creative Destruction Lab Rapid Screening Consortium (CDL RSC), a cooperative, non-for-profit initiative, formed in Canada in August 2020 to help workplaces manage the COVID-19 crisis.…”

“…By contrast, RAS can overcome the biases in case ascertainment attributable to self-report or PCR testing by encompassing near real-time monitoring of asymptomatic transmission. While the main interventions for limiting the spread of COVID-19 in the workplace include social distancing, housekeeping and sanitation, use of PPE, restricting site access, and ventilation, 5,44 RAS represents a promising approach for preventing asymptomatic infectious individuals from unwittingly transmitting the virus to their colleagues at work or to their families within the household 2,45 by offering an additional layer of protection alongside existing measures 2,34,46 . Moreover, coupled with a data system, it can provide broader surveillance of viral transmission and potentially inform on industry- or job-specific variation in the implementation of other measures 47 …”

Artificial intelligence adoption in a monopoly market

“…In reality, such predictions are rarely perfect and this has implications for decisions made, for example,Lowenthal (1982) andGans (2022b). Here, however, because of the complexity of the pricing and quantity decisions, the focus is on the first-order impacts of the adoption of perfect AI prediction of demand.5Lim (1980) refers to this as P-behaviour.…”