Background Rapid antigen (RA) tests are being increasingly employed to detect SARS-CoV-2 infections in quarantine and surveillance. Prior research has focused on RT-PCR testing, a single RA test, or generic diagnostic characteristics of RA tests in assessing testing strategies. Methods We have conducted a comparative analysis of the post-quarantine transmission, the effective reproduction number during serial testing, and the false-positive rates for 18 RA tests with emergency use authorization from The United States Food and Drug Administration and an RT-PCR test. To quantify the extent of transmission, we developed an analytical mathematical framework informed by COVID-19 infectiousness, test specificity, and temporal diagnostic sensitivity data. Results We demonstrate that the relative effectiveness of RA tests and RT-PCR testing in reducing post-quarantine transmission depends on the quarantine duration and the turnaround time of testing results. For quarantines of two days or shorter, conducting a RA test on exit from quarantine reduces onward transmission more than a single RT-PCR test (with a 24-h delay) conducted upon exit. Applied to a complementary approach of performing serial testing at a specified frequency paired with isolation of positives, we have shown that RA tests outperform RT-PCR with a 24-h delay. The results from our modeling framework are consistent with quarantine and serial testing data collected from a remote industry setting. Conclusions These RA test-specific results are an important component of the tool set for policy decision-making, and demonstrate that judicious selection of an appropriate RA test can supply a viable alternative to RT-PCR in efforts to control the spread of disease.

In laboratory bioassays, four carabid species [Agonum dorsale (Pontoppidan), Bembidion lampros (Herbst), B. obtusum Serville, and Demetrias atricapillus (L.)] that are important predators of aphids in cereals in the United Kingdom were exposed to deposits of deltamethrin, dimethoate, or pirimicarb on glass for up to 72 h. We detected differences between compounds and species that are discussed in the context of exposure of these predators to insecticides in the field. We also describe problems involved in obtaining comparative toxicity data when dilutions of field application rates for target species are used in bioassays with nontarget species. Such problems add another dimension to risk assessment based on laboratory data.

: Industrial firefighters share many characteristics with municipal firefighters; however, employers frequently have not addressed or characterized the unique job duties, hazards, and specific physical/mental demands associated with industrial firefighting. In addition, gaps exist in the medical literature with regard to industrial firefighter demographics, behavioral risk factors, and chronic diseases. Finally, the proper methodologies for fitness-for-duty assessment of employees acting in this capacity are lacking. To address these gaps, the American College of Occupational and Environmental Medicine (ACOEM) convened a Task Force in 2014, to develop fitness-for-duty guidance for industrial firefighters. This document highlights these gaps and suggests research opportunities to enhance the health and safety of this population. While an extensive literature review found a lack of studies for this population-thus excluding the development of an evidence-based document-sufficient materials were available from which to draw preliminary conclusions, considerations for best practices, and recommendations for future studies.

Rapid antigen (RA) tests are being increasingly employed for detection of COVID-19 infections in implementations of quarantine and surveillance. We conducted a comparative analysis of quarantine durations, testing frequencies, and false-positive rates for all of the 18 RA tests for which emergency use authorization (EUA) has been given by the FDA and a nasopharyngeal RT-PCR test. For each test, we employed a mathematical model of imminent infections to calculate the effective reproductive number in the context of the test used for quarantine or serial testing strategy. We informed the model with data on test specificity and temporal diagnostic sensitivity, convolved with a data-driven profile of COVID-19 infectiousness across the disease time course. Our results demonstrate that the relative effectiveness of RA and RT-PCR tests in reducing post-quarantine transmission depends on the duration of quarantine and the turnaround time of testing results. When quarantines are shorter than five days, our results suggest that an RA test on entry to and on exit from quarantine would reduce onward transmission more than a single RT-PCR test conducted upon exit. Conducting surveillance via serial RT-PCR testing with a 24-h turnaround time, the testing frequency paired with isolation of positives that is required to suppress the effective reproduction number (RE) below one was found to require a minimum frequency of every six days. RA tests reduce RE below one when conducted at a minimum frequency that ranges from every six days to every eight days—depending on the type of RA test—with a median of seven days. Our analysis also highlights that the risk of onward transmission during serial testing increases with the delay in obtaining the results. False-positives were found to be more frequent with RA tests, an issue that could be mitigated with clinical and RT-PCR follow-up. Accounting for the specific diagnostic traits of RA tests, they are an important component of the tool set for policy decision-making, and can serve as a viable alternative to RT-PCR in efforts to control the spread of disease.

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