Seroprevalence as an Indicator of Undercounting of COVID-19 Cases in a Large Well-Described Cohort.

Introduction: Reported confirmed cases represent a small portion of overall true cases for many infectious diseases. The undercounting of true cases can be considerable when a significant portion of infected individuals are asymptomatic or minimally symptomatic, as is the case with COVID-19. Seroprevalence studies are an efficient way to assess the extent to which true cases are undercounted during a large-scale outbreak and can inform efforts to improve case identification and reporting. Methods: A longitudinal seroprevalence study of active duty U.S. military members was conducted from May 2020 through June 2021. A random selection of service member serum samples submitted to the Department of Defense Serum Repository was analyzed for the presence of antibodies reactive to SARS-CoV-2. The monthly seroprevalence rates were compared with those of cumulative confirmed cases reported during the study period. Results: Seroprevalence was 2.3% in May 2020 and increased to 74.0% by June 2021. The estimated true case count based on seroprevalence was 9.3 times greater than monthly reported cases at the beginning of the study period and fell to 1.7 by the end of the study. Conclusions: In our sample, confirmed case counts significantly underestimated true cases of COVID-19. The increased availability of testing over the study period and enhanced efforts to detect asymptomatic and minimally symptomatic cases likely contributed to the fall in the seroprevalence to reported case ratio.

Incidence and Management of Chronic Insomnia, Active Component, U.S. Armed Forces, 2012 to 2021.

The Department of Veterans Affairs and Department of Defense Clinical Practice Guideline (VA/DOD CPG) provides evidence-based management pathways to mitigate the negative consequences of common sleep disorders among service members (SMs). This retrospective cohort study estimated the incidence of chronic insomnia in active component military members from 2012 through 2021 and the percentage of SMs receiving VA/DOD CPG-recommended insomnia treatments. During this period, 148,441 incident cases of chronic insomnia occurred, with an overall rate of 116.1 per 10,000 person-years (p-yrs). A sub-analysis of SMs with chronic insomnia diagnosed during 2019-2020 found that 53.9% received behavioral therapy and 72.7% received pharmacotherapy. As case ages increased, the proportion who received therapy decreased. Co-existing mental health conditions increased the likelihood of receiving therapy for insomnia cases. Clinician education about the VA/DOD CPG may improve utilization of these evidence-based management pathways for SMs with chronic insomnia.