CHA – Children’s Hospital Academic Medical Organization
CHA-21-002 – Establishing the true prevalence of SARS-CoV-2 infection in Ontario reproductive age women through newborn blood spot antibody testing
In order to complete the proposed project of providing population infection rate surveillance of COVID-19 using residual newborn screening dried blood spots (DBS), a validated assay in the Newborn Screening Ontario (NSO) laboratory was required. We had connected with Wallac Oy Perkin Elmer, a market-leader in the field of newborn screening, prior to proposing the project, and they indicated that they had a potential assay under development. However, at the time of project start, the assay was not fully validated for use on DBS and the performance was not fully established. We therefore first pursued a Health Canada regulated device validation trial to establish this (with funding support and sponsorship from Perkin Elmer). This step was vital as newborn screening DBS would not have been permitted to be shipped in the required numbers to an off-site laboratory for validation testing. The kit, in the end, will not be submitted for Health Canada approval, but will be available as an investigational use only assay. It is now feasible to rapidly implement the investigational kit in the NSO laboratory.
We have completed validation work on the Perkin Elmer investigational use only kit in the NSO laboratory. This kit allows measurement of anti-SARS-CoV-2 lgG and lgM antibodies using two 3 mm punches from dried blood spot (DBS)samples taken on Whatman 903 paper. With NSO’s infrastructure using DBS cards and Perkin Elmer equipment, the kit was incorporated into existing testing workflows at NSO. It was feasible to rapidly implement DBS testing in our laboratory for anti-SARS-CoV-2 antibodies. Theoretically, this could likewise be applied in other jurisdictions with established DBS newborn screening programs using Perkin Elmer equipment. We also worked with Dr. Marc-Andre Langlois to successfully adapt and validate the high-specificity anti-covid lgG/lgM/lgA ELISA assay that he has developed for use on DBS.
For assay validation, samples were procured from various sources for testing. This included prospective, self-collected adult samples and pre-2019 NSO newborn screening samples. We demonstrated the feasibility of self-collected DBS sample kits, without the added expense or increased health risks of prospectively collecting additional samples from participants. We also established sample handling, processing, and storage procedures for these samples.
Public Health Measures and Society
Primary Project Lead for Contact