Publications by authors named "Sylvie Nancy Beaulac"
Background: There is a need to understand the duration of infectivity of primary and recurrent coronavirus disease 2019 (COVID-19) and identify predictors of loss of infectivity.
Methods: Prospective observational cohort study with serial viral culture, rapid antigen detection test (RADT) and reverse transcription polymerase chain reaction (RT-PCR) on nasopharyngeal specimens of healthcare workers with COVID-19. The primary outcome was viral culture positivity as indicative of infectivity.
Evaluation of the performance of multiple immunoassay diagnostic platforms on the National Microbiology Laboratory SARS-CoV-2 National Serology Panel.
J Assoc Med Microbiol Infect Dis Can
September 2022
Article Synopsis
- Serological assays for detecting SARS-CoV-2 antibodies are crucial for surveys and need thorough evaluations to ensure quality and accuracy in testing.
- The study involved distributing plasma/serum samples from confirmed SARS-CoV-2 infections to various laboratories in Canada and the U.S. to assess their performance while keeping the results blinded.
- Results showed that most high-throughput assays had excellent sensitivity, with Roche, Ortho, and Siemens achieving 100%, and overall, the serological tests used in public health settings displayed acceptable sensitivity and excellent specificity.
Background: Accurate and practical biologic tools to estimate HIV incidence is crucial to better monitor the epidemic and evaluate the effectiveness of HIV prevention and treatment programs.
Methods: We evaluated two avidity assays to measure recent HIV infection: the Sedia HIV-1 LAg-Avidity EIA (Sedia Biosciences, Portland) and the Centers for Disease Control and Prevention (CDC)-modified Bio-Rad-Avidity assay (Bio-Rad Laboratories, Mississauga, ON). Longitudinal specimens (n = 473) obtained from 123 treatment-naive seroconverted individuals enrolled in the Primary HIV-1 Infection (PHI) cohort of Quebec were used to determine the average time an individual is considered to be recently infected (mean duration of recent infection; MDRI), for the two avidity assays alone and in combination using a nonparametric survival method analysis.