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- Page navigation anchor for RE: A better normal in Canada will need a better detection system for emerging and re-emerging respiratory pathogensRE: A better normal in Canada will need a better detection system for emerging and re-emerging respiratory pathogens
We agree with Berry et al that re-assessment of how we monitor emerging pathogens is needed.
We note that blood donor surveillance was not specifically mentioned in their article. Between May 2020 and September 2022, Canadian Blood Services in partnership with the COVID-19 Immunity Task Force (CITF) tested samples from all Canadian provinces (except for Quebec and the territories) for SARS-CoV-2 antibodies [1-2]. Monthly reports were openly and routinely distributed to provincial and national public health professionals, posted on the CITF website and used to estimate the population prevalence of SARS-CoV-2 in mathematical models.
The authors note wastewater surveillance provided an excellent immediate indicator of increased infections but not the proportion of people infected. We assert that blood donor sero-surveillance has provided timely, geographically broad, regular measurement of nucleocapsid and spike antibodies.
An ideal detection system for emerging pathogens would allow for the linking of health administration data (e.g. vaccine history and molecular testing). Canadian Blood Services is undertaking a pilot study to link SARS-CoV-2 seroprevalence data to administrative data from at least one province. Blood donors are a convenient low-cost option for near-national blood sample collection almost every day of the year [3]. Canadian Blood Services is responsible for blood collection in all provinces except Quebec (and the territories), thus...
Show MoreCompeting Interests: None declared.References
- 1. Reedman CN, Drews SJ, Yi QL, et al. Changing patterns of SARS-CoV-2 seroprevalence among Canadian blood donors during the vaccine era. Microbiol Spectr 2022:10;e0033922.
- 2. O’Brien SF, Caffrey N, Yi QL, et al. SARS-CoV-2 seroprevalence among Canadian blood donors: The advance of Omicron. Viruses 2022;14:2336.
- 3. O’Brien SF, Drews SJ. Lewin A, et al. Canadian blood suppliers: An expanding role in public health surveillance? Can Commun Dis Rep 2022;48:124-30.
- 4. O’Brien SF, Drews SJ, Lewin A, et al. How do we decide how representative our donors are for public health surveillance? Transfusion 2022;doi: 10.1111/trf.17140.
- 5. Grant R, Dub T, Andrianou X, et al. SARS-CoV-2 population-based seroprevalence studies in Europe: A scoping review. BMJ Open 2021:11;e045245.
- Page navigation anchor for RE: A better normal in Canada will need a better detection system for emerging and re-emerging respiratory pathogensRE: A better normal in Canada will need a better detection system for emerging and re-emerging respiratory pathogens
We enjoyed the article by Berry et al. and agree that expanded surveillance systems are needed for effective and equitable public health policy moving forward [1]. The authors highlight that wastewater surveillance has been an innovative public-health tool and can detect early transmission of SARS-CoV-2 in the community. We agree and believe that additional environmental testing using the built environment can play a complementary role.
Our team has validated a method of environmental sampling for SARS-CoV-2 in which the floor is swabbed and then processed using quantitative polymerase chain reaction (qPCR) [2]. Our initial study showed that hospital COVID-19 burden is reflected in built environment samples, particularly from floors. [2] These findings have been replicated and in one study they identified that there was a 67-fold higher odds of detecting SARS-CoV2 from the floor compared to other surfaces in the built environment [3]. Floors likely act as a “sink” and collect the droplets and aerosols produced from infected individuals when they eventually fall to the floor. Swabbing the floor is simple and takes approximately 30 seconds per swab and then processed in the lab using standard approaches.[2] In contrast to wastewater surveillance, our approach has greater spatial resolution, fewer logistical challenges (e.g., does not require access to sewage), minimal up-front costs, and doesn’t require installation of equipment or a device for the building.
...Show MoreCompeting Interests: Our work has been supported by a project grant from CIHR, an NSERC alliance grant, and an NSERC discovery grant, CoVaRRNet, The Ottawa Hospital Academic Medical Organization (TOHAMO), and Northern Ontario Academic Medical Association (NOAMA). MF is a consultant for ProofDx, a start-up company that has created a point-of-care test for COVID-19 using CRISPR.References
- [1] Berry I, Brown KA, Buchan SA, et al. A better normal in Canada will need a better detection system for emerging and re-emerging respiratory pathogens. CMAJ. 2022 Sept; 194(36): E1250–E1254.
- [2] Hinz A, Xing L, Doukhanine E, et al. SARS-CoV-2 detection from the built environment and wastewater and its use for hospital surveillance. FACETS. 2022 Jan; 7 (1): 82-97.
- [3] Ziegler MJ, Huang E, Bekele S, et al. Spatial and temporal effects on severe acute respiratory coronavirus virus 2 (SARS-CoV-2) contamination of the healthcare environment. Infect Control Hosp Epidemiol. Cambridge University Press; 2021 Dec; 1–6.
- [4] Fralick M, Nott C, Moggridge J, et al. Detection of COVID-19 Outbreaks in Long-Term Care Homes Using Built Environment Testing for SARS-CoV-2: A Multicentre Prospective Study. medRxiv. 2022 Jun.