AbstractAs part of a multi-year surveillance program of tick-borne diseases, we describe babesia surveillance of blood donors using nucleic acid tests conducted in 2025 and summarize cases of babesiosis reported by public health officials in Nova Scotia, Canada, from 2023 through 2025. Among 10,976 blood donor specimens, one specimen, collected from a blood donor in Nova Scotia Health's Western Zone, was positive, although this result was unable to be confirmed. Since babesiosis became reportable in Nova Scotia on May 23, 2023, eleven clinical cases have been documented, including eight in individuals who resided in the Western Zone and had no recent history of travel.

This dual-center study evaluated the impact of artificial intelligence (AI) on urine culture turnaround times in Canadian diagnostic laboratories using microbiology laboratory automation. Data were collected before and after the implementation of PhenoMATRIX (PM), an AI-based software that provides continuous culture sorting and result interpretation support. In both a low-volume tertiary care hospital and a high-volume community laboratory, PM enabled earlier availability of interpretable results; however, reductions in time to result reporting (TTRR) were contingent on workflows for result release. At the tertiary care site, implementation of PM alone was associated with increased TTRR, reflecting delays between result availability and reporting. Integration of PM+ enabled automated release of negative results as they became available, resulting in a TTRR reduction of approximately 1.3 h. At the community laboratory, where PM+ was not implemented, a TTRR improvement of approximately 5.3 h was achieved by advancing manual screening workflows (08:00 vs 16:00), facilitating earlier review and release of PM-generated results. These findings indicate that AI-driven culture assessment reduces TTRR when coupled with processes that enable timely result release, either through automated reporting or optimized laboratory review workflows.IMPORTANCEAdvances in artificial intelligence (AI), coupled with the power of laboratory automation, is the next step in the evolution of the clinical microbiology laboratory. We demonstrated that bacterial culture assessment (urine cultures) by AI decreases the time required to release results to clinicians and reduces the hands-on time required by technologists to analyze and finalize laboratory analysis. This study was performed in two different laboratories that differed not only in geography but also in scope and scale. The same ultimate benefits were seen in both institutions demonstrating that this technology is widely applicable for most laboratories.

Bartonella quintana is a louse-borne Gram-negative bacterium first discovered as the cause of trench fever during World War I. As B. quintana is not identified using routine culture with 5-day incubation, the pathogen is an agent of blood culture-negative endocarditis, particularly among individuals experiencing homelessness. Here, we describe a case of an 80-year-old man who presented in the winter of 2017 with severe aortic valve regurgitation resulting in exercise intolerance, requiring aortic valve replacement. Pathological assessment of the explanted aortic valve revealed changes of infective endocarditis. The presence of B. quintana in the valve tissue was confirmed using molecular methods including B. quintana-specific polymerase chain reaction (PCR) as well as PCR and sequencing of the 16S rRNA, heat shock protein (hsp), and RNA polymerase (rpoB) genes. The organism was subsequently grown from the patient's blood. Serology revealed B. quintana IgG titres that were initially elevated at 1:4096, but decreased and were sustained at 1:1024, as the patient recovered following treatment with doxycycline and rifampin. Bartonella quintana endocarditis is recognized as a cause of culture-negative endocarditis, but the diagnosis can be difficult, as symptoms may be non-specific, and the organism requires special conditions (and media) for routine growth. This case emphasizes the value of pathological investigations and microbiology laboratory support in the setting of low clinical and intraoperative suspicion of infective endocarditis.

Lyme disease (LD), a tick-borne infection, is endemic in Nova Scotia. One decade ago, the seropositivity rate to Borrelia burgdorferi was 2/1855 (0.14%). In the current study, using residual sera representing ages 10-64 years, we demonstrate an increase in seroprevalence, to 25/1872 (1.60%), with the highest seroprevalence in the western area of the province.

In hospitals, identification of methicillin-resistant Staphylococcus aureus (MRSA) is important to reduce possible transmissions and serious outcomes. Traditional culture and susceptibility testing requires 48-72 h, whereas Xpert MRSA polymerase chain reaction (PCR) can provide accurate MRSA detection in <1 h. Unfortunately, the high cost of such commercial PCRs precludes their use in many laboratories. Using MRSA as a model, this study hypothesized that specimen pooling in a setting of low prevalence could reduce PCR costs and provide rapid results. A total of 424 sequential nasal/groin specimens submitted for MRSA detection were subjected to routine culture-based detection using chromogenic media, and suspect colonies were confirmed using mass spectrometry and cefoxitin disk diffusion testing. These specimens were also pooled 1:8 or processed individually by Xpert MRSA PCR. Analytical sensitivity of PCR with and without pooling was compared to culture using triplicate 10-fold serial dilutions of an MRSA reference strain. The analytical sensitivity and clinical performance of specimen pooling paired with Xpert MRSA PCR were equivalent to traditional culture-based detection. Of specimen pools, 66.0% (35/53) were MRSA negative, and 34.0% (18/53) were MRSA positive. Pool resolution by PCR showed similar results as culture, identifying 116 MRSA-negative and 28 MRSA-positive specimens. At a prevalence of 6.6% (28/424), 1:8 specimen pooling with Xpert PCR provided equivalent results to culture-based methods and reduced the overall number of PCR reactions by 53.5%. Compared to individual PCR testing, specimen pooling would lower overall PCR costs, but the feasibility of this approach and the extent of benefits afforded would depend on MRSA prevalence.IMPORTANCEIdentifying antibiotic-resistant bacteria like methicillin-resistant Staphylococcus aureus (MRSA) is important to prevent their spread and potentially life-threatening infections. MRSA can be detected using bacterial culture and antibiotic susceptibility testing but requires up to 3 days for results. Molecular detection methods like polymerase chain reaction (PCR) are more rapid (<1 h), but their high cost prevents implementation for many laboratories. To reduce PCR costs, specimen pooling was considered. With specimen pooling, swabs from multiple individuals are combined and tested together. If pools are negative, all their members are considered negative. If pools are positive, each swab is tested individually to identify the one(s) with MRSA. By reducing the number of PCRs required, pooling reduces PCR costs. In this study, 6.7% of samples were MRSA positive, and pooling reduced overall PCR costs by 54%, provided results in 1-2 h, and identified the same number of MRSA cases as the comparator (i.e., culture).

Curricular guidelines promote standardized approaches to coverage of essential knowledge and skills in undergraduate education. The American Society for Microbiology (ASM) Curriculum Guidelines for Undergraduate Microbiology were developed in 2012. Continuous, rapid growth of knowledge in science and a dynamic, changing world necessitate updates to these guidelines. As such, ASM formed a task force in the summer of 2022. The task force assessed the 2012 ASM Curriculum Guidelines considering advancements in technology, an understanding of an expanded role of microbes, and a broader scope addressing relevant social and environmental aspects of microbiology. Language in the updated guidelines was also modified to better include eukaryotic microbes, viruses, and other acellular microbes. The task force formed working groups, each aimed at revising specific sections of the 2012 ASM Curriculum Guidelines. The revisions to the ASM Curriculum Guidelines were reviewed by subject matter experts and education stakeholders. Feedback from this peer review was incorporated into the updated guidelines, and further comments were solicited from the ASM Conference of Undergraduate Educators (ASMCUE) attendees in November 2023 before these guidelines were finalized. In this article, we describe the rationale and development of updated ASM Curriculum Guidelines which identify foundational concepts that will serve to improve microbial literacy and that can be expanded upon to address more advanced and specialized topics.

ABSTRACT Antigen-based rapid diagnostic tests (Ag-RDTs) were widely deployed to enhance SARS-CoV-2 testing capacity during the COVID-19 pandemic. Consistent with national guidance for low prevalence settings, positive Ag-RDTs were confirmed using nucleic acid amplification tests (NAATs) to avoid false positive results. However, increasing demands for positive Ag-RDT confirmation competed with other testing priorities in clinical laboratories. This work hypothesized that real-time RT-PCR without nucleic acid extraction (NAE) would be sufficiently sensitive to support positive Ag-RDT confirmation. Ag-RDT and NAAT results from community-based asymptomatic testing sites prior to the omicron variant wave were compared to calculate the weekly false positive rate (FPR) and false detection rate (FDR). Real-time RT-PCR was compared with and without NAE using 752 specimens previously tested positive for SARS-CoV-2 using commercial NAATs and 344 specimens from Ag-RDT-positive individuals. The impact of SARS-CoV-2 prevalence on laboratory resources required to sustain Ag-RDT confirmation was modeled for the RT-PCR with and without NAE. Overall, FPR was low [0.07% (222/330,763)] in asymptomatic testing sites, but FDR was high [30.7% (222/724)]. When RT-PCR was compared with and without NAE, 100% concordance was obtained with NAAT-positive specimens, including those from Ag-RDT-positive individuals. NAE-free RT-PCR significantly reduced time to results, human resources, and overall costs. A 30.7% FDR reaffirms the need for NAAT-based confirmation of positive Ag-RDT results during low SARS-CoV-2 prevalence. NAE-free RT-PCR was shown to be a simple and cost-sparing NAAT-based solution for positive Ag-RDT confirmation, and its implementation supported data-driven broader Ag-RDT deployment into communities, workplaces, and households. IMPORTANCE Rapid antigen testing for SARS-CoV-2 was widely deployed during the COVID-19 pandemic. In settings of low prevalence, national guidance recommends that positive antigen test results be confirmed with molecular testing. Given the high testing burden on clinical laboratories during the COVID-19 pandemic, the high volume of positive antigen tests submitted for confirmatory testing posed challenges for laboratory workflow. This study demonstrated that a simple PCR method without prior nucleic acid purification is an accurate and cost-effective solution for positive rapid antigen test confirmation. Implementing this method allowed molecular confirmatory testing for positive antigen tests to be sustained as antigen testing was expanded into large populations such as workplaces, schools, and households.

Background Respiratory viral illness (RVI)—e.g., influenza, COVID-19—is a serious threat in long-term care (LTC) facilities. Standard infection control measures are suboptimal in LTC facilities because of residents’ cognitive impairments, care needs, and susceptibility to loneliness and mental illness. Further, LTC residents living with high degrees of frailty who contract RVIs often develop the so-called atypical symptoms (e.g., delirium, worse mobility) instead of typical cough and fever, delaying infection diagnosis and treatment. Although far-UVC (222 nm) light devices have shown potent antiviral activity in vitro, clinical efficacy remains unproven. Methods Following a study to assay acceptability at each site, this multicenter, double-blinded, cluster-randomized, placebo-controlled trial aims to assess whether far-UVC light devices impact the incidence of RVIs in LTC facilities. Neighborhoods within LTC facilities are randomized to receive far-UVC light devices (222 nm) or identical placebo light devices that emit only visible spectrum light (400–700 nm) in common areas. All residents are monitored for RVIs using both a standard screening protocol and a novel screening protocol that target atypical symptoms. The 3-year incidence of RVIs will be compared using intention-to-treat analysis. A cost-consequence analysis will follow. Discussion This trial aims to inform decisions about whether to implement far-UVC light in LTC facilities for RVI prevention. The trial design features align with this pragmatic intent. Appropriate additional ethical protections have been implemented to mitigate participant vulnerabilities that arise from conducting this study. Knowledge dissemination will be supported through media engagement, peer-reviewed presentations, and publications. Trial registration ClinicalTrials.gov NCT05084898. October 20, 2021.

Background: Occult bacterial infection is a proposed etiology of low back pain (LBP). However, a causative link between LBP and bacteria remains unconfirmed. Herein, we determined the incidence of occult discitis in patients receiving surgery for LDH. Methods: Study Design: prospective cohort study. Inclusion criteria: consecutive adult patients undergoing discectomy for symptomatic LDH. Exclusion criteria: prior epidural steroid use, prior spinal surgery, and antibiotic use within 2 weeks of surgery. Tissue samples: Four nuclear tissue and ligamentum flavum (control) samples were obtained per patient using stringent aseptic protocol. Samples underwent 16S-PCR and culturing. Results: Eighty-one patients were enrolled (mean age 43.3±13.3 years). All (100%) of tissue samples were negative by 16S PCR and no virulent species were detected. Nuclear and ligament cultures were both negative in 51 (62.9%) cases. Cultures were positive for nuclear tissue only, ligament only, or both in 14.8%, 12.3%, and 9.9% of cases, respectively. Fifteen of 20 (75%) disc positive samples grew a single colony of an indolent species. Conclusions: The findings of this prospective cohort study of consecutive patients receiving surgery for LDH do not support the theory of occult discitis. All samples were 16S-PCR negative, and most cultures were negative or grew a single colony suggestive of contamination.

BACKGROUND:Mpox (formerly monkeypox) is an emerging zoonotic disease of public health concern that presents as a rash mimicking other common viral exanthems. Unlike traditional testing algorithms relying on several assays, the BioFire FilmArray meningitis/encephalitis (ME) panel simultaneously detects common viruses causing rashes; however, Biofire ME is only licensed for testing on cerebral spinal fluid.OBJECTIVES:This study evaluated use of the Biofire ME panel for detection and discrimination of herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), varicella zoster virus (VZV), human herpesviruses type 6 (HHV-6), enteroviruses (EVs), and human paraechoviruses (HPeVs) from a dermal or mucocutaneous swabs collected in universal transport media (UTM).STUDY DESIGN:Results of the BioFire ME panel were compared against methods used during clinical testing. Ten-fold serial dilutions in UTM of cultured viruses were used to compare analytical sensitivity, and analytical specificity was assessed using panels of microorganisms in UTM. Clinical sensitivity and specificity were assessed using 20 positive specimens each for HHV-1, HHV-2, HHV-6, VZV, EVs, and HPeV, as well as 35 known negative specimens that included 15 mpox-positive specimens.RESULTS:Biofire ME was as sensitive as comparator methods, and correctly discriminated all HSV-1, HSV-2, VZV, HHV-6, EVs, and HPeVs from mpox and mpox-mimickers. Cross-reaction between EV and rhinoviruses A, B, and C were noted in the specificity panel.CONCLUSIONS:Swabs in UTM collected for mpox testing are suitable for use on the Biofire ME panel, allowing more streamlined diagnostic testing for viral exanthems in patients under investigation for mpox infection.

ABSTRACT During the COVID-19 pandemic, SARS-CoV-2 detection using nucleic acid amplification tests (NAATs) played a key role in clinical management and public health interventions. However, mutations could jeopardize NAAT-based detection if they occur in the NAAT target site, potentially resulting in false negative results. However, mutation monitoring is challenged as the exact location of commercial NAAT target sites is not divulged by manufacturers. This study sequenced commercial SARS-CoV-2 NAAT target sites to assess the impact of mutations occurring in these regions. The resulting sequences for the Xpert, Cobas, and ID NOW SARS-CoV-2 assays were queried against SARS-CoV-2 genome databases to identify mutations in circulating strains. Synthetic DNAs and clinical specimens harboring NAAT target site mutations were used to assess mutation impact. Of 17,600 NAAT target site mutation occurrences in a genome database, 269 compromised target detection. These represented 24 unique mutations that reduced NAAT target sensitivity and nine led to target detection failure. Only seven of these mutations were previously recognized. Overall, this reactive strategy along with passive surveillance identified 29 novel mutations that compromised detection with Xpert and Cobas targets. Knowledge of commercial NAAT target sites, paired with a strategy for mutation impact assessment and ongoing genetic surveillance, provided a robust framework for commercial NAAT target site quality assurance. The question remains of who should be responsible for NAAT target site quality assurance, but collaborative efforts between methods users, industry, and regulatory agencies would be ideal. IMPORTANCE Molecular tests like polymerase chain reaction were widely used during the COVID-19 pandemic but as the pandemic evolved, so did SARS-CoV-2. This virus acquired mutations, prompting concerns that mutations could compromise molecular test results and be falsely negative. While some manufacturers may have in-house programs for monitoring mutations that could impact their assay performance, it is important to promptly report mutations in circulating viral strains that could adversely impact a diagnostic test result. However, commercial test target sites are proprietary, making independent monitoring difficult. In this study, SARS-CoV-2 test target sites were sequenced to monitor and assess mutations impact, and 29 novel mutations impacting SARS-CoV-2 detection were identified. This framework for molecular test target site quality assurance could be adapted to any molecular test, ensuring accurate diagnostic test results and disease diagnoses.

ABSTRACT In hospitals during the COVID-19 pandemic, laboratory testing was important to reduce SARS-CoV-2 transmissions, particularly for high-risk settings like the emergency department and pre-operative settings and for the safe return to work of exposed healthcare workers (HCWs). For these applications, delayed test results from laboratory nucleic acid amplification tests (NAATs) posed a barrier to maximizing efficient patient flow and minimizing staffing shortages. This quality improvement project sought to evaluate the performance of the Lucira Check-It COVID-19 Test, a rapid diagnostic test that used NAAT technology (NAAT-RDT). Using 10-fold serial dilutions of SARS-CoV-2, the analytical sensitivity of the NAAT-RDT was assessed against standard NAATs used for routine diagnostic testing. Clinical performance was assessed at two Nova Scotia hospitals in 405 cases with paired swabs tested by NAAT-RDT and laboratory-based NAATs. These represented three distinct populations: patients presenting to the emergency department (n = 208), patients in the pre-operative setting (n = 158), and patients presenting to community testing sites (n = 38). The analytical sensitivity of the NAAT-RDT and other laboratory NAATs was comparable. During clinical evaluation, the overall sensitivity and specificity were 92.9% and 98.3%, respectively, with little variation between settings. The Lucira NAAT-RDT is a portable and self-contained device that provides an easily interpreted result within 30 minutes following a bilateral nasal swab collection. Its performance was shown to be acceptable for use in three settings in this quality improvement project, facilitating patient flow and management. IMPORTANCE In hospitals during the COVID-19 pandemic, laboratory testing was important to reduce SARS-CoV-2 transmissions, while facilitating patient flow in the emergency department and pre-operative settings, and allowing for the safe return to work of exposed healthcare workers. Delayed test results from laboratory nucleic acid amplification tests (NAATs) posed a barrier to maximizing efficient patient flow and minimizing staffing shortages. This quality improvement project sought to evaluate the analytical and clinical performance of the Lucira Check-It COVID-19 Test, a point-of-care test that used NAAT technology, in the perioperative setting, emergency department, and community testing sites. We found the Lucira Check-It to have comparable performance to laboratory NAATs. It can be employed with little training for specimen collection, processing, and interpretation, and at a cost justifiable from the resources saved from avoiding sample transport and laboratory testing.

# CPSS-1. Abstract ID 108. Radiographic reporting in adolescent idiopathic scoliosis: Is there a discrepancy between radiologists’ reports and surgeons’ assessments? {#article-title-2} Cobb angle measurement is a standard method for quantification of scoliosis in patients with adolescent

Containment measures employed during the COVID-19 pandemic included prompt recognition of cases, isolation, and contact tracing. Bilateral nasal (NA) swabs applied to a commercial antigen-based rapid diagnostic test (Ag-RDT) offer a simpler and more comfortable alternative to nasopharyngeal (NP) collection; however, little is known about the sensitivity of this method in an asymptomatic population. Participants in community-based asymptomatic testing sites were screened for SARS-CoV-2 using an Ag-RDT with NP sampling. Positive individuals returned for confirmatory molecular testing and consented to repeating the Ag-RDT using a bilateral NA swab for comparison. Residual test buffer (RTB) from Ag-RDTs was subjected to real-time reverse transcription-PCR (RT-PCR). Of 123,617 asymptomatic individuals, 197 NP Ag-RDT-positive participants were included, with 175 confirmed positive by RT-PCR. Of these cases, 154 were identified from the NA swab collection with Ag-RDT, with a sensitivity of 88.0% compared to the NP swab collection. Stratifying results by RT-PCR cycle threshold demonstrated that sensitivity of the nasal collection method varied based on the cycle threshold (C-T) value of the paired RT-PCR sample. RT-PCR testing on the RTB from the Ag-RDT using NP and NA swab collections resulted in 100.0% and 98.7% sensitivity, respectively. NA swabs provide an adequate alternative to NP swab collection for use with Ag-RDT, with the recognition that the test is most sensitive in specimens with high viral loads. With the high sensitivity of RT-PCR testing on RTB from Ag-RDT, a more streamlined approach to confirmatory testing is possible without recollection or use of paired collections strategies. IMPORTANCE Nasal swabbing for SARS-CoV-2 (COVID-19) comes with many benefits but is slightly less sensitive than traditional nasopharyngeal swabbing; however, confirmatory lab-based testing could be performed directly from the residual buffer from either sample type.

Abstract Objective: To identify preventable factors that contribute to the cross transmission of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) to patients in healthcare facilities. Design: A case–control study was conducted among inpatients on a coronavirus disease 2019 (COVID-19) outbreak unit. Setting: This study was conducted in a medical-surgical unit of a tertiary-care hospital in Nova Scotia in May 2021. Patients: Patients hospitalized on the unit for at least 12 hours and healthcare workers (HCW) working on the unit within 2 weeks of outbreak declaration were included. Methods: Risk factors for SARS-CoV-2 infection were analyzed using simple and multiple logistic regression. Whole-genome sequencing (WGS) was performed to identify SARS-CoV-2 strain relatedness. Network analysis was used to describe patient accommodation. Results: SARS-CoV-2 infections were identified in 21 patients (29.6%) and 11 HCWs (6.6%). WGS data revealed 4 distinct clades of related sequences. Several factors likely contributed to the outbreak, including failure to identify SARS-CoV-2, a largely incomplete or unvaccinated population, and patient wandering behaviors. The most significant risk factor for SARS-CoV-2 infection was room sharing with an infectious patient, which was the only factor that remained statistically significant following multivariate analysis (odds ratio [OR], 9.2l; 95% confidence interval [CI], 2.04–41.67; P = .004). Conclusions: This outbreak likely resulted from admission of 2 patients with COVID-19, with subsequent transmissions to 17 patients and 11 staff. WGS and bioinformatics analyses were critical to identifying previously unrecognized nosocomial transmissions of SARS-CoV-2. This study supports strategies to reduce nosocomial transmissions of SARS-CoV-2, such as single-patient rooms, promotion of COVID-19 vaccination, and infection prevention and control measures including management of wandering behaviors.

Antigen-based rapid diagnostic tests (Ag-RDTs) have been widely used for the detection of SARS-CoV-2 during the coronavirus disease 2019 (COVID-19) pandemic. In settings of low disease prevalence, such as asymptomatic community testing, national guidelines recommend confirmation of positive Ag-RDT results with a nucleic acid amplification test (NAAT). This often requires patients to be recalled for repeat specimen recollection and subsequent testing in reference laboratories. This project assessed the use of a point-of-care molecular NAAT for SARS-CoV-2 detection (i.e., ID NOW), which was performed on-site at a volunteer-led asymptomatic community testing site on the residual test buffer (RTB) from positive Ag-RDTs. The ID NOW NAAT assay was performed on RTB from two Ag-RDTs: the Abbott Panbio and BTNX Rapid Response assays. Results of ID NOW were compared to real-time RT-PCR at a reference laboratory. Along with investigations into the clinical performance of ID NOW on RTB, analytical specificity was assessed with a panel of various respiratory organisms. Of the Ag-RDTs results evaluated, all 354 Ag-RDTs results characterized as true positives by RT-PCR were accurately identified with ID NOW testing of RTB. No SARS-CoV-2 detections by ID NOW were observed from 10 specimens characterized as false-positive Ag-RDTs, or from contrived specimens with various respiratory organisms. The use of on-site molecular testing on RTB provides a suitable option for rapid confirmatory testing of positive Ag-RDTs, thereby obviating the need for specimen recollection for molecular testing at local reference laboratories. IMPORTANCE During the COVID-19 pandemic, rapid antigen tests have been widely used for the detection of SARS-CoV-2. These simple devices allow rapid test results. However, false-positive results may occur. As such, individuals with positive rapid tests often must return to testing centers to have a second swab collected, which is then transported to a specialized laboratory for confirmation using molecular tests. As an alternative to requiring a repeat visit and a prolonged turn-around time for result confirmation, this project evaluated whether the leftover material from rapid antigen tests could be confirmed directly on a portable point-of-care molecular instrument. Using this approach, molecular confirmation of positive antigen tests could be performed in less than 15 min, and the results were equivalent to laboratory-based confirmation. This procedure eliminates the need for individuals to return to testing centers following a positive rapid antigen test and ensures accurate antigen test results through on-site confirmation.

The COVID-19 pandemic has been hallmarked by several waves of variants of concern (VoCs), each with novel challenges. Currently, the highly transmissible Omicron VoC is predominant worldwide, and sore throat is common, among other cold-like symptoms. Anecdotes on social media have suggested that sampling one's throat can increase the sensitivity for Omicron detection by antigen-based rapid testing devices (Ag-RDTs). This work aimed to improve the local testing strategy and determine whether the sensitivity of Ag-RDTs designed for nasal sampling is altered with the use of self-administered throat swabs in self-perceived asymptomatic individuals. This investigation used a common Ag-RDT (i.e., Abbott Panbio COVID-19 Ag rapid test device) to compare three sampling sites: nasal swab, throat swab, and combined nasal/throat. All Ag-RDT results were confirmed with molecular testing from residual test buffer. Compared to reverse transcriptase PCR (RT-PCR), samples from nasal or throat swabs each detected 64.5% of SARS-CoV-2 cases; however, combining the contributions of each swab increased the positive percent agreement (PPA) with RT-PCR to 88.7%. This trend was also evident with the Rapid Response Ag-RDT (BTNX), which uses more flexible swabs than does the Panbio. When nasal swab collection was compared to paired sampling of the nose/throat using a single swab with the Panbio Ag-RDT, the PPAs were 68.4% and 81.6%, respectively. No false-positive results were observed with nasal, throat, or combined nasal/throat sampling. Self-administered throat and nasal/throat swabs both had >90% acceptability. These findings support the use of self-collected combined nasal/throat sampling for Ag-RDT-based SARS-CoV-2 detection in self-perceived asymptomatic individuals. IMPORTANCE This quality project demonstrates that combining the results of nasal and throat swabs or using a combined single swab of the throat and nares resulted in increased detection of SARS-CoV-2 using a rapid antigen test, in an asymptomatic population. Importantly, no false positives were detected, and over 90% of people were willing to perform the combination swab. These types of projects are instrumental in informing local practices to improve testing strategies. These data support the option of using a combined nasal/throat swab in our local setting to enhance the detection of Omicron.

Given the global shortage of nasopharyngeal (NP) swabs typically used for respiratory virus detection, alternative collection methods were evaluated during the COVID-19 pandemic. This study showed that a combined oropharyngeal/nares swab is a suitable alternative to NP swabs for the detection of SARS-CoV-2, with sensitivities of 91.7% and 94.4%, respectively.