BACKGROUND: Serial testing for SARS-CoV-2 is recommended to reduce spread of the virus; however, little is known about adherence to recommended testing schedules and reporting practices to health departments. OBJECTIVE: The Self-Testing for Our Protection from COVID-19 (STOP COVID-19) study aims to examine adherence to a risk-based COVID-19 testing strategy using rapid antigen tests and reporting of test results to health departments. METHODS: STOP COVID-19 is a 12-week digital study, facilitated using a smartphone app for testing assistance and reporting. We are recruiting 20,000 participants throughout the United States. Participants are stratified into high- and low-risk groups based on history of COVID-19 infection and vaccination status. High-risk participants are instructed to perform twice-weekly testing for COVID-19 using rapid antigen tests, while low-risk participants test only in the case of symptoms or exposure to COVID-19. All participants complete COVID-19 surveillance surveys, and rapid antigen results are recorded within the smartphone app. Primary outcomes include participant adherence to a risk-based serial testing protocol and percentage of rapid tests reported to health departments. RESULTS: As of February 2022, 3496 participants have enrolled, including 1083 high-risk participants. Out of 13,730 tests completed, participants have reported 13,480 (98.18%, 95% CI 97.9%-98.4%) results to state public health departments with full personal identifying information or anonymously. Among 622 high-risk participants who finished the study period, 35.9% showed high adherence to the study testing protocol. Participants with high adherence reported a higher percentage of test results to the state health department with full identifying information than those in the moderate- or low-adherence groups (high: 71.7%, 95% CI 70.3%-73.1%; moderate: 68.3%, 95% CI 66.0%-70.5%; low: 63.1%, 59.5%-66.6%). CONCLUSIONS: Preliminary results from the STOP COVID-19 study provide important insights into rapid antigen test reporting and usage, and can thus inform the use of rapid testing interventions for COVID-19 surveillance.

Background: There is a need to understand the performance of rapid antigen tests (Ag-RDT) for detection of the Delta (B.1.61.7; AY.X) and Omicron (B.1.1.529; BA1) SARS-CoV-2 variants. Methods: Participants without any symptoms were enrolled from October 18, 2021 to January 24, 2022 and performed Ag-RDT and RT-PCR tests every 48 hours for 15 days. This study represents a non-pre-specified analysis in which we sought to determine if sensitivity of Ag-RDT differed in participants with Delta compared to Omicron variant. Participants who were positive on RT-PCR on the first day of the testing period were excluded. Delta and Omicron variants were defined based on sequencing and date of first RT-PCR positive result (RT-PCR+). Comparison of Ag-RDT performance between the variants was based on sensitivity, defined as proportion of participants with Ag-RDT+ results in relation to their first RT-PCR+ result, for different duration of testing with rapid Ag-RDT. Subsample analysis was performed based on the result of participants' second RT-PCR test within 48 hours of the first RT-PCR+ test. Results: From the 7,349 participants enrolled in the parent study, 5,506 met the eligibility criteria for this analysis. A total of 153 participants were RT-PCR+ (61 Delta, 92 Omicron); among this group, 36 (23.5%) tested Ag-RDT+ on the same day, and 84 (54.9%) tested Ag-RDT+ within 48 hours as first RT-PCR+. The differences in sensitivity between variants were not statistically significant (same-day: Delta 16.4% [95% CI: 8.2-28.1] vs Omicron 28.2% [95% CI: 19.4-38.6]; and 48-hours: Delta 45.9% [33.1-59.2] vs. Omicron 60.9% [50.1-70.9]). This trend continued among the 86 participants who had consecutive RT-PCR+ result (48-hour sensitivity: Delta 79.3% [60.3-92.1] vs. Omicron: 89.5% [78.5-96.0]). Conversely, the 38 participants who had an isolated RT-PCR+ remained consistently negative on Ag-RDT, regardless of the variant. Conclusions: The performance of Ag-RDT is not inferior among individuals infected with the SARS-CoV-2 Omicron variant as compared to the Delta variant. The improvement in sensitivity of Ag-RDT noted with serial testing is consistent between Delta and Omicron variant. Performance of Ag-RDT varies based on duration of RT-PCR+ results and more studies are needed to understand the clinical and public health significance of individuals who are RT-PCR+ for less than 48 hours.

The dynamics of SARS-CoV-2 replication and shedding in humans remain poorly understood. We captured the dynamics of infectious virus and viral RNA shedding during acute infection through daily longitudinal sampling of 60 individuals for up to 14 days. By fitting mechanistic models, we directly estimate viral reproduction and clearance rates, and overall infectiousness for each individual. Significant person-to-person variation in infectious virus shedding suggests that individual-level heterogeneity in viral dynamics contributes to superspreading. Viral genome load often peaked days earlier in saliva than in nasal swabs, indicating strong compartmentalization and suggesting that saliva may serve as a superior sampling site for early detection of infection. Viral loads and clearance kinetics of B.1.1.7 and non-B.1.1.7 viruses in nasal swabs were indistinguishable, however B.1.1.7 exhibited a significantly slower pre-peak growth rate in saliva. These results provide a high-resolution portrait of SARS-CoV-2 infection dynamics and implicate individual-level heterogeneity in infectiousness in superspreading.

BACKGROUND: Serial screening is critical for restricting spread of SARS-CoV-2 by facilitating the timely identification of infected individuals to interrupt transmission chains. The variation in sensitivity of different diagnostic tests at different stages of infection has not been well documented. METHODS: This is a longitudinal study of 43 adults newly infected with SARS-CoV-2. All participants provided daily samples for saliva and nasal swab RTqPCR, Quidel SARS Sofia antigen FIA, and live virus culture. RESULTS: We show that both RTqPCR and the Quidel SARS Sofia antigen FIA peak in sensitivity during the period in which live virus is detected in nasal swabs, but the sensitivity of RTqPCR tests rises more rapidly prior to this period. We also estimate the sensitivities of RTqPCR and antigen tests as a function of testing frequency. CONCLUSIONS: RTqPCR tests are more effective than antigen tests at identifying infected individuals prior to or early during the infectious period and thus for minimizing forward transmission (given timely results reporting). All tests showed > 98% sensitivity for identifying infected individuals if used at least every three days. Daily screening using antigen tests can achieve ~90% sensitivity for identifying infected individuals while they are viral culture positive.

The COVID-19 pandemic caused more than 30 million infections in the United States between March 2020 and April 2021. In response to systemic disparities in SARS-CoV2 testing and COVID-19 infections, health systems, city leaders and community stakeholders in Worcester, Massachusetts created a citywide Equity Task Force with a specific goal of making low-barrier testing available to individuals throughout our community. Within months, the state of Massachusetts announced the Stop the Spread campaign, a state-funded testing venture. With this funding, and through our community-based approach, our team tested more than 48,363 individuals between August 3, 2020 and February 28, 2021. Through multiple PDSA (Plan-Do-Study-Act) cycles, we optimized our process to test close to 300 individuals per hour. Our positivity rate ranged from 1.5% with our initial testing events to a high of 13.4% on January 6, 2021. During the challenges of providing traditional inpatient and ambulatory care during the pandemic, our health system, city leadership, and community advocacy groups united to broaden the scope of care to include widespread, population-based SARS-CoV2 testing. We anticipate that the lessons learned in conducting this testing campaign can be applied to further surges of SARS-CoV2, international environments, and future respiratory disease pandemics.

BACKGROUND: Agitated behaviors are frequently encountered in the prehospital setting and require emergent treatment to prevent harm to patients and prehospital personnel. Chemical sedation with ketamine works faster than traditional pharmacologic agents, though it has a higher incidence of adverse events, including intubation. Outcomes following varying initial doses of prehospital intramuscular (IM) ketamine use have been incompletely described. OBJECTIVE: To determine whether using a lower dose IM ketamine protocol for agitation is associated with more favorable outcomes. METHODS: This study was a pre-/post-intervention retrospective chart review of prehospital care reports (PCRs). Adult patients who received chemical sedation in the form of IM ketamine for agitated behaviors were included. Patients were divided into two cohorts based on the standard IM ketamine dose of 4mg/kg and the lower IM dose of 3mg/kg with the option for an additional 1mg/kg if required. Primary outcomes included intubation and hospital admission. Secondary outcomes included emergency department (ED) length of stay, additional chemical or physical restraints, assaults on prehospital or ED employees, and documented adverse events. RESULTS: The standard dose cohort consisted of 211 patients. The lower dose cohort consisted of 81 patients, 17 of whom received supplemental ketamine administration. Demographics did not significantly differ between the cohorts (mean age 35.14 versus 35.65 years; P = .484; and 67.8% versus 65.4% male; P = .89). Lower dose subjects were administered a lower ketamine dose (mean 3.24mg/kg) compared to the standard dose cohort (mean 3.51mg/kg). There was no statistically significant difference between the cohorts in intubation rate (14.2% versus 18.5%; P = .455), ED length of stay (14.31 versus 14.88 hours; P = .118), need for additional restraint and sedation (P = .787), or admission rate (26.1% versus 25.9%; P = .677). In the lower dose cohort, 41.2% (7/17) of patients who received supplemental ketamine doses were intubated, a higher rate than the patients in this cohort who did not receive supplemental ketamine (8/64, 12.5%; P < .01). CONCLUSION: Access to effective, fast-acting chemical sedation is paramount for prehospital providers. No significant outcomes differences existed when a lower dose IM ketamine protocol was implemented for prehospital chemical sedation. Patients who received a second dose of ketamine had a significant increase in intubation rate. A lower dose protocol may be considered for an agitation protocol to limit the amount of medication administered to a population of high-risk patients.

The National Institutes of Health (NIH) launched the Rapid Acceleration of Diagnostics (RADx SM ) Tech initiative to support the development and commercialization of novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) point-of-care test devices. The primary objective of the Clinical Studies Core (CSC) was to perform SARS-CoV-2 device studies involving diverse populations and settings. Within a few months, the infrastructure for clinical studies was developed, including a master protocol, digital study platform, data management system, single IRB, and multi-site partnerships. Data from some studies are being used to support Emergency Use Authorization of novel SARS-CoV-2 test devices. The CSC reduced the typical time and cost of developing medical devices and highlighted the impactful role of academic and NIH partnership in addressing public health needs at a rapid pace during a global pandemic. The structure, deployment, and lessons learned from this experience are widely applicable to future in vitro diagnostic device clinical studies.

What is already known about this topic?: Diagnostic tests and sample types for SARS-CoV-2 vary in sensitivity across the infection period. What is added by this report?: We show that both RTqPCR (from nasal swab and saliva) and the Quidel SARS Sofia FIA rapid antigen tests peak in sensitivity during the period in which live virus can be detected in nasal swabs, but that the sensitivity of RTqPCR tests rises more rapidly in the pre-infectious period. We also use empirical data to estimate the sensitivities of RTqPCR and antigen tests as a function of testing frequency. What are the implications for public health practice?: RTqPCR tests will be more effective than rapid antigen tests at identifying infected individuals prior to or early during the infectious period and thus for minimizing forward transmission (provided results reporting is timely). All modalities, including rapid antigen tests, showed > 94% sensitivity to detect infection if used at least twice per week. Regular surveillance/screening using rapid antigen tests 2-3 times per week can be an effective strategy to achieve high sensitivity ( > 95%) for identifying infected individuals.

INTRODUCTION: There is concern about the initiation of opiates in healthcare settings due to the risk of future misuse. Although opiate medications have historically been at the core of prehospital pain management, several states are introducing non-opiate alternatives to prehospital care. Prior studies suggest that non-opiate analgesics are non-inferior to opiates for many acute complaints, yet there is little literature describing practice patterns of pain management in prehospital care. Our goal was to describe the practice patterns and attitudes of paramedics toward pain management after the introduction of non-opiates to a statewide protocol. METHODS: This study was two-armed. The first arm employed a pre/post retrospective chart review model examining medication administrations reported to the Massachusetts Ambulance Trip Information System between January 1, 2017-December 31, 2018. We abstracted instances of opiate and non-opiate utilizations along with patients' clinical course. The second arm consisted of a survey administered to paramedics one year after implementation of non-opiates in the state protocol, which used binary questions and Likert scales to describe beliefs pertaining to prehospital analgesia. RESULTS: Pain medications were administered in 1.6% of emergency medical services incidents in 2017 and 1.7% of incidents in 2018. The rate of opiate analgesic use was reduced by 9.4% in 2018 compared to 2017 (90.6% vs 100.0%). The absolute reduction in opiate use in 2018 was 3.6%. Women were less likely (odds ratio [OR] = 0.78, 95% confidence interval [CI], 0.69-0.89) and trauma patients were more likely to receive opiates (OR = 2.36, CI, 1.96-2.84). Mean transport times were longer in opiate administration incidents (36.97 vs 29.35 minutes, t = 17.34, p < 0.0001). We surveyed 100 paramedics (mean age 41.98, 84% male). Compositely, 85% of paramedics planned to use non-opiates and 35% reported having done so. Participants planning to use non-opiates were younger and less experienced. Participants indicated that concern about adverse effects, efficacy, and time to effect impacted their practice patterns. CONCLUSION: The introduction of non-opiate pain medication to state protocols led to reduced opiate administration. Men and trauma patients were more likely to receive opiates. Paramedics reported enthusiasm for non-opiate medications. Beliefs about non-opioid analgesics pertaining to adverse effects, onset time, and efficacy may influence their utilization.