Prevalence of COVID-19 and Long COVID in Collegiate Student Athletes from Spring 2020 to Fall 2021: A Retrospective Survey

Symptomatic COVID-19 and post-COVID conditions, also referred to as post-acute sequelae of SARS-CoV-2 (PASC) or Long COVID, have been widely reported in young, healthy people, but their prevalence has not yet been determined in student athletes. We surveyed a convenience sample of 18 collegiate school administrators, representing about 7,000 student athletes. According to their survey responses, 9.8% of student athletes tested positive for COVID-19 in spring 2020 and 25.4% tested positive in the academic year of fall 2020 to spring 2021. About 4% of student athletes who tested positive from spring 2020 to spring 2021 developed Long COVID, defined as new, recurring, or ongoing physical or mental health consequences occurring 4 or more weeks after SARS-CoV-2 infection. This study highlights that Long COVID occurs in healthy collegiate athletes and merits a larger study to determine population-wide prevalence.

COVID Testing in the Workplace: Return to Work Testing in an Occupational Cohort

BackgroundThe Omicron SARS-CoV-2 variant resulted in significant community-based transmission. Numerous occupational settings have employed surveillance testing strategies to minimize occupational exposure and return workers safely to work following isolation. MethodsFrom an occupational COVID-19 testing program, we obtained longitudinal (February 2021-January 2022) saliva-based RT-qPCR results and starting December 27th, 2021, daily on-site molecular over-the-counter (OTC) nasal swab-based isothermal nucleic acid amplification test (molecular OTC; Cue Health COVID-19 test) results. We quantified the fraction of tests with PCR cycle threshold (Ct) values <30 on each day post detection from suspected and confirmed Omicron infections (n=37), compared results to molecular OTC testing, and measured workplace and household transmission. We evaluated return-to-work timing using a post-isolation, two-test threshold of Ct >30, or two negative molecular OTC tests over a 24 hour period, or a single PCR test >30 plus negative molecular OTC test. ResultsFrom the paired testing cohort, 37 (48%) individuals tested positive; all 37 were vaccinated. All individuals tested positive [≤]1 day after a previous negative test, and 19 (51.3%) remained PCR-positive with Ct values <30 at day 5. While 3 (8.1%) remained PCR-positive with a Ct value <30 on day 10, no individuals remained PCR-positive on day 12. The average time to PCR clearance/return-to-work was 7.94 days (median=9.5 days). Time to clearance for those boosted (n=8; 7.75 days) and those not yet boosted (8.04 days) did not differ (p=0.49). Peak viral load measured by PCR was 1.97 days from the initial positive test. There were no cases of transmission after returning to work. ConclusionsA large percentage of individuals remain contagious at day 5 post first positive test based on serial PCR testing and can continue until day 12. Early discontinuation of isolation can utilize a two test framework separated by 24 hours. Rapid onsite tests may be useful.

Discordant SARS-CoV-2 PCR and Rapid Antigen Test Results When Infectious: A December 2021 Occupational Case Series

The performance of Covid-19 diagnostic tests must continue to be reassessed with new variants of concern. The objective of this study was to describe the discordance in saliva SARS-CoV-2 PCR and nasal rapid antigen test results during the early infectious period. We identified a high-risk occupational case cohort of 30 individuals with daily testing during an Omicron outbreak in December 2021. Based on viral load and transmissions confirmed through epidemiological investigation, most Omicron cases were infectious for several days before being detectable by rapid antigen tests.

Pooled Surveillance Testing Program for Asymptomatic SARS-CoV-2 Infections in K-12 Schools and Universities

The negative impact of continued school closures during the height of the COVID-19 pandemic warrants the establishment of new cost-effective strategies for surveillance and screening to safely reopen and monitor for potential in-school transmission. Here, we present a novel approach to increase the availability of repetitive and routine Covid-19 testing that may ultimately reduce the overall viral burden in the community. We describe implementation of a testing program that included students, faculty and staff from K-12 schools and universities participating in the SalivaClear pooled surveillance method (Mirimus Clinical Labs, Brooklyn, NY). Over 400,000 saliva specimens were self-collected from students, faculty and staff from 93 K-12 schools and 18 universities and tested in pools of up to 24 samples over a 20-week period during this pandemic. Peaks of positive cases were seen in the days following the Halloween, Thanksgiving and New Year holidays. Pooled testing did not significantly alter the sensitivity of the molecular assay in terms of both qualitative (100% detection rate on both pooled and individual samples) and quantitative (comparable cycle threshold (CT) values between pooled and individual samples) measures. Pooling samples substantially reduced the costs associated with PCR testing and allowed schools to rapidly assess transmission and adjust prevention protocols as necessary. By establishing low-cost, weekly testing of students and faculty, pooled saliva analysis enabled schools to determine whether transmission had occurred, make data-driven decisions, and adjust safety protocols. Pooled testing is a fundamental component to the reopening of schools, minimizing transmission among students and faculty.

SalivaDirect: Simple and sensitive molecular diagnostic test for SARS-CoV-2 surveillance

Current bottlenecks for improving accessibility and scalability of SARS-CoV-2 testing include diagnostic assay costs, complexity, and supply chain shortages. To resolve these issues, we developed SalivaDirect, which received Emergency Use Authorization (EUA) from the U.S. Food and Drug Administration on August 15th, 2020. The critical component of our approach is to use saliva instead of respiratory swabs, which enables non-invasive frequent sampling and reduces the need for trained healthcare professionals during collection. Furthermore, we simplified our diagnostic test by (1) not requiring nucleic acid preservatives at sample collection, (2) replacing nucleic acid extraction with a simple proteinase K and heat treatment step, and (3) testing specimens with a dualplex quantitative reverse transcription PCR (RT-qPCR) assay. We validated SalivaDirect with reagents and instruments from multiple vendors to minimize the risk for supply chain issues. Regardless of our tested combination of reagents and instruments from different vendors, we found that SalivaDirect is highly sensitive with a limit of detection of 6-12 SARS-CoV-2 copies/L. When comparing SalivaDirect to paired nasopharyngeal swabs using the authorized ThermoFisher Scientific TaqPath COVID-19 combo kit, we found high agreement in testing outcomes (>94%). In partnership with the National Basketball Association (NBA) and Players Association, we conducted a large-scale (n = 3,779) SalivaDirect usability study and comparison to standard nasal/oral tests for asymptomatic and presymptomatic SARS-CoV-2 detection. From this cohort of healthy NBA players, staff, and contractors, we found that 99.7% of samples were valid using our saliva collection techniques and a 89.5% positive and >99.9% negative test agreement to swabs, demonstrating that saliva is a valid and noninvasive alternative to swabs for large-scale SARS-CoV-2 testing. SalivaDirect is a flexible and inexpensive ($1.21-$4.39/sample in reagent costs) option to help improve SARS-CoV-2 testing capacity. Register to become a designated laboratory to use SalivaDirect under our FDA EUA on our website: publichealth.yale.edu/salivadirect/.