There was no evidence of interference from potentially interfering substances at the concentrations listed above, and no cross-reactivity was observed against samples containing antibodies to common pathogens including seasonal coronaviruses and other respiratory viruses such as influenza A and B

There was no evidence of interference from potentially interfering substances at the concentrations listed above, and no cross-reactivity was observed against samples containing antibodies to common pathogens including seasonal coronaviruses and other respiratory viruses such as influenza A and B. The high specificity of Anti-CoV2 arises due to the multiple binding steps that have to occur for the antibodies to be detected. Positive percent agreement (PPA) and unfavorable Hbg1 percent agreement (NPA) were calculated along with the corresponding exact two-sided 95 % confidence intervals (CI) using an FDA Emergency Use Authorized PCR test as the reference method. Anti-CoV2 was shown to have 100 % sensitivity (PPA; 95 % CI 88.4C100 %) and 100 % specificity (NPA; 95 % CI 95.2C100 %). Against 157 pre-pandemic samples, no cross-reactivity was observed with seasonal coronaviruses or other respiratory pathogens Nylidrin Hydrochloride tested. Additionally, no interference was observed when samples were spiked with: conjugated bilirubin 0.4 mg/ml; unconjugated bilirubin 0.4 mg/ml; hemoglobin 5 mg/ml; prednisolone 0.12 mg/ml; triglycerides 15 mg/ml. In conclusion, Anti-CoV2 provides accurate qualitative detection of total antibodies against SARS-CoV-2. Keywords: SARS-CoV-2, COVID-19, Antibody, Serological screening 1.?Introduction Severe acute respiratory syndrome Nylidrin Hydrochloride coronavirus 2 (SARS-CoV-2) is a novel beta-coronavirus that has caused a global outbreak of respiratory disease, Coronavirus Disease 2019 (COVID-19), with significant morbidity, mortality, and excess healthcare costs [1,2]. An important aspect of controlling and slowing the spread of this pandemic is the availability of reliable and accurate methods for screening both symptomatic and asymptomatic individuals [[3], [4], [5]]. Rapid detection of cases and contacts, along with appropriate clinical management and contamination control efforts, are crucial to public health and disease control [4,5]. Despite experts working around the clock, much is usually yet to be discovered regarding SARS-CoV-2 transmission dynamics, ability to confer antibody production and immunity, and even prevalence of the disease within our communities. In patients infected with SARS-CoV-2, quick, successive seroconversion of specific immunoglobulin A (IgA), immunoglobulin M (IgM) and immunoglobulin (IgG) typically occur within 14 days post onset of symptoms (DPO), with IgA responses appearing earlier, larger and more sustained than IgM [[6], [7], [8], [9], [10], [11]]. Strength of antibody responses likely correlates with disease severity [[12], [13], [14], [15]]. In a study of 259 symptomatic North American patients infected with SARS-CoV-2, ELISA-based detection of IgG, IgA, or IgM antibody responses to the receptor binding domain name of the SARS-CoV-2 spike protein were all accurate in identifying infected individuals 14C28 DPO, with 100 % specificity and a sensitivity of 97 %, 91 %, and 81 %, respectively [8]. In the same study, IgG responses persisted through 75 DPO [8]. Currently, antibody testing is not recommended as the sole basis for diagnosis of acute SARS-CoV-2 infection, and as such no antibody assessments are authorized by the US Food and Drug Administration (FDA) for this purpose [16]. However, antibody assessments may be used in conjunction with molecular assessments as a diagnostic aid, Nylidrin Hydrochloride particularly in patients with delayed presentation and where viral genomic weight is usually below the limit of detection for PCR assays, and to facilitate contact tracing, surveillance and sero-epidemiologic studies [[16], [17], [18]]. They are important for detecting past contamination, including those without symptoms, as well as identifying convalescent plasma donors, and for verifying successful vaccinations once one is developed [[16], [17], [18], [19]]. Lateral circulation assays (LFAs) are portable, easy to use and provide a quick readout, making them ideal point-of-care (POC) serological assessments [20]. However, current LFAs are run individually, sensitivity and specificity varies between assays, and there is subjectivity by individual readers when calling faint bands [20]. Worryingly, clinical overall performance and sensitivity issues for some COVID-19 LFAs have been noted, and a FDA removed test list has been created [21]. In a meta-analysis of 40 studies, pooled sensitivity for.