ABSTRACT
Appropriate use and interpretation of serological tests for assessments of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exposure, infection and potential immunity require accurate data on assay performance. We conducted a head-to-head evaluation of ten point-of-care-style lateral flow assays (LFAs) and two laboratory-based enzyme-linked immunosorbent assays to detect anti-SARS-CoV-2 IgM and IgG antibodies in 5-d time intervals from symptom onset and studied the specificity of each assay in pre-coronavirus disease 2019 specimens. The percent of seropositive individuals increased with time, peaking in the latest time interval tested (>20 d after symptom onset). Test specificity ranged from 84.3% to 100.0% and was predominantly affected by variability in IgM results. LFA specificity could be increased by considering weak bands as negative, but this decreased detection of antibodies (sensitivity) in a subset of SARS-CoV-2 real-time PCR-positive cases. Our results underline the importance of seropositivity threshold determination and reader training for reliable LFA deployment. Although there was no standout serological assay, four tests achieved more than 80% positivity at later time points tested and more than 95% specificity.
Subject(s)
Betacoronavirus , Clinical Laboratory Techniques/methods , Coronavirus Infections/diagnosis , Pneumonia, Viral/diagnosis , Adult , Aged , Aged, 80 and over , Antibodies, Viral/blood , Betacoronavirus/genetics , Betacoronavirus/immunology , Betacoronavirus/isolation & purification , Biotechnology , COVID-19 , COVID-19 Testing , Chromatography, Affinity , Clinical Laboratory Techniques/statistics & numerical data , Coronavirus Infections/epidemiology , Coronavirus Infections/immunology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Male , Middle Aged , Pandemics , Pneumonia, Viral/epidemiology , Pneumonia, Viral/immunology , Point-of-Care Testing , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2 , Sensitivity and Specificity , Young AdultABSTRACT
BACKGROUND: Serological tests are crucial tools for assessments of SARS-CoV-2 exposure, infection and potential immunity. Their appropriate use and interpretation require accurate assay performance data. METHOD: We conducted an evaluation of 10 lateral flow assays (LFAs) and two ELISAs to detect anti-SARS-CoV-2 antibodies. The specimen set comprised 128 plasma or serum samples from 79 symptomatic SARS-CoV-2 RT-PCR-positive individuals; 108 pre-COVID-19 negative controls; and 52 recent samples from individuals who underwent respiratory viral testing but were not diagnosed with Coronavirus Disease 2019 (COVID-19). Samples were blinded and LFA results were interpreted by two independent readers, using a standardized intensity scoring system. RESULTS: Among specimens from SARS-CoV-2 RT-PCR-positive individuals, the percent seropositive increased with time interval, peaking at 81.8-100.0% in samples taken >20 days after symptom onset. Test specificity ranged from 84.3-100.0% in pre-COVID-19 specimens. Specificity was higher when weak LFA bands were considered negative, but this decreased sensitivity. IgM detection was more variable than IgG, and detection was highest when IgM and IgG results were combined. Agreement between ELISAs and LFAs ranged from 75.7-94.8%. No consistent cross-reactivity was observed. CONCLUSION: Our evaluation showed heterogeneous assay performance. Reader training is key to reliable LFA performance, and can be tailored for survey goals. Informed use of serology will require evaluations covering the full spectrum of SARS-CoV-2 infections, from asymptomatic and mild infection to severe disease, and later convalescence. Well-designed studies to elucidate the mechanisms and serological correlates of protective immunity will be crucial to guide rational clinical and public health policies.
ABSTRACT
Lesbian, gay, bisexual, transgender, queer, and intersex (LGBTQI) individuals continue to face barriers to accessing appropriate and comprehensive healthcare. Compounding this problem, healthcare trainees report few training opportunities and low levels of preparedness to care for LGBTQI patients. In 2009, an interprofessional group of students and a faculty advisor at the University of California, San Francisco, developed a novel student-organized LGBTQI Health Forum for medical, dental, pharmacy, nursing, and physical therapy students to deliver LGBTQI health content that was otherwise absent from the formal curriculum. This elective course has evolved based upon participant feedback, emerging educational strategies, and the existing curricula infrastructure at our institution. After eight years of growth, this 10-contact hour weekend elective attracts over 250 participants each year. Plenary sessions deliver foundational terminology and skills to all attendees. Learners then select breakout sessions to attend, allowing for an individualized curriculum based upon specific interests and knowledge gaps. Breakout session topics prioritize traditionally underrepresented aspects of LGBTQI health in professional school curricula. This Forum serves as a model in which to supplement LGBTQI content into existing school curricula and offers an opportunity for interprofessional education. Next steps include conducting a formal evaluation of the curriculum, expanding our performance-based assessments, and potentially implementing a continuing education program for licensed practitioners. With a core group of interprofessional student organizers and a faculty champion, other institutions may view this course architecture as a potential way to offer learners not only LGBTQI content, but other underrepresented subjects into their own educational programs.
