RESUMO
Limitations in timely testing for SARS-CoV-2 drive the need for new approaches in suspected COVID-19 disease. We queried whether viral load (VL) in the upper airways at presentation could improve the management and diagnosis of patients. This study was conducted in a 9 hospital system in Allegheny County, Pennsylvania between March 1-August 31 2020. Viral load was determined by PCR assays for patients presenting to the Emergency Departments (ED), community pediatrics practices and college health service. We found that for the ED patients, VL did not vary substantially between those admitted and not. VL was relatively equivalent across ages, except for the under 25 age groups that tended to present with higher loads. To determine if rapid antigen testing (RAT) could aid diagnosis in certain populations, we compared BD Veritor and Quidel Sofia to SOC PCR-based tests. The antigen assay provided a disease-detection sensitivity of >90% in a selection of 32 positive students and was modeled to have an 80% sensitivity in all positive students. In the outpatient pediatric population, the antigen assay detected 70% of PCR-positives. Extrapolating these findings to viral loads in older hospitalized patients, a minority would be detected by RAT (40%). Higher loads did correlate with death, though the prognostic value was marginal (ROC AUC of only 0.66). VL did not distinguish between those needing mechanical ventilation and routine inpatients. We conclude that VL in upper airways, while not prognostic for disease management, may aid in selecting proper testing methodologies for certain patient populations.
RESUMO
ObjectiveA small percentage of universities and colleges conduct mass SARS-CoV-2 testing. However, universal testing is resource-intensive, strains national testing capacity, and false negative tests can encourage unsafe behaviors. ParticipantsA large urban university campus. MethodsVirus control centered on three pillars: mitigation, containment, and communication, with testing of symptomatic and a random subset of asymptomatic students. ResultsRandom surveillance testing demonstrated a prevalence among asymptomatic students of 0.4% throughout the term. There were two surges in cases that were contained by enhanced mitigation and communication combined with targeted testing. Cumulative cases totaled 445 for the term, most resulting from unsafe undergraduate student behavior and among students living off-campus. A case rate of 232/10,000 undergraduates equaled or surpassed several peer institutions that conducted mass testing. ConclusionsAn emphasis on behavioral mitigation and communication can control virus transmission on a large urban campus combined with a limited and targeted testing strategy.
