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Background: Measurement of SARS-CoV-2 antibody seropositivity is important to accurately understand exposure to infection and/or vaccination in specific populations. This study aimed to estimate the serologic response to SARS-CoV-2 virus infection and vaccination in children in Calgary, Alberta over a two-year period., Methods: Children with or without prior SARS-CoV-2 infections, were enrolled in Calgary, Canada in 2020. Venous blood was sampled 4 times from July 2020 to April 2022 for SARS-CoV-2 nucleocapsid and spike antibodies. Demographic and clinical information was obtained including SARS-CoV-2 testing results and vaccination records., Results: 1035 children were enrolled and 88.9% completed all 4 visits; median age 9 years (IQR: 5,13); 519 (50.1%) female; and 815 (78.7%) Caucasian. Before enrolment, 118 (11.4%) had confirmed or probable SARS-CoV-2. By April 2022, 39.5% of previously uninfected participants had a SARS-CoV-2 infection. Nucleocapsid antibody seropositivity declined to 16.4% of all infected children after more than 200 days post diagnosis. Spike antibodies remained elevated in 93.6% of unvaccinated infected children after more than 200 days post diagnosis. By April 2022, 408 (95.6%) children 12 years and older had received 2 or more vaccine doses, and 241 (61.6%) 5 to 11 year-old children had received 2 vaccine doses. At that time, all 685 vaccinated children had spike antibodies, compared with 94/176 (53.4%) of unvaccinated children., Conclusions: In our population, after the first peak of Omicron variant infections and introduction of COVID-19 vaccines for children, all vaccinated children, but just over one-half of unvaccinated children, had SARS-CoV-2 spike antibodies indicating infection and/or vaccination, highlighting the benefit of vaccination. It is not yet known whether a high proportion of seropositivity at the present time predicts sustained population-level protection against future SARS-CoV-2 transmission, infection or severe COVID-19 outcomes in children., Competing Interests: “I have read the journal’s policy and the authors of this manuscript have the following competing interests: JDK has been an investigator on research projects funded by GlaxoSmithKline, Merck, Moderna, and Pfizer. All funds have been paid to his institute, and he has not received any personal payments. JDK is an unpaid member of the Canadian COVID-19 Immunity Task Force. JD has been an investigator on a research project funded by Moderna. All funds have been paid to her institute, and she has not received any personal payments. CC has been an investigator on research projects funded by Merck. All funds have been paid to her institute, and she has not received any personal payments. All other authors declare no competing interests.”, (Copyright: © 2023 Doucette et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Context: A regional centralized laboratory service for the rapid diagnosis of malaria was implemented 3 years ago in May 1999 within the Division of Microbiology, Calgary Laboratory Services., Objective: To describe the design and performance of this unique microbiology laboratory service., Design: Blood specimens must arrive at the central laboratory within 2 hours of collection. Thin blood smears are read and reported from suspected acute cases within 1 hour of receipt, 24 hours per day, 7 days a week, by trained and experienced microbiology technologists. All positive malaria smears are reviewed by a medical microbiologist and confirmed by polymerase chain reaction at a reference laboratory., Setting: Calgary Laboratory Services provides integrated laboratory services to the Calgary Health Region, an urban area of more than 1 million people., Main Outcome Measures: Performance of the service has been continuously monitored by measuring preanalytic and analytic test turnaround times, test accuracy, clinical relevance, and the results of proficiency testing., Results: More than 90% of blood specimens for malaria from community locations have consistently arrived within 2 hours of collection, and hospitals have reached this target within the past year. Although polymerase chain reaction was more sensitive at detecting the presence of malaria, the expert microscopists were as accurate at determining the type of Plasmodium infection. More than 95% of all positive smear results are consistently reported within 2 hours of receipt of a blood specimen., Conclusions: Implementation of a regional centralized microbiology service has improved our ability to make a rapid and accurate diagnosis of malaria in this region.

Study Objective: To compare and contrast the modes of death in a neonatal (NICU) and a pediatric (PICU) intensive care unit., Design: Retrospective analysis of patient records., Subjects: All newborn infants and children (< 17 years of age) who died in the NICU and PICU at the University of Alberta Hospitals, Edmonton, between Jan. 1, 1990, to Dec. 31, 1991., Results: The mortality rate in the PICU was 8.7% (73/839) compared with 5.6% (75/1333) in the NICU (p = 0.007). Withdrawal of therapy was the most common cause of death in both units and occurred more commonly in the NICU (NICU = 69% vs PICU = 34%; p = 0.01). There were significantly more deaths as a result of failed cardiopulmonary resuscitation (CPR) in the PICU than in the NICU (29% vs 13%; p = 0.046). Death after no-CPR orders occurred with equal frequency in both units (NICU 17%; PICU 15%). Brain death accounted for 22% (16/87) of PICU deaths; no infant in the NICU was declared brain dead (p < 0.05). When deaths resulting from brain death and failed CPR were excluded, there was no significant difference between the two units regarding withdrawal of therapy (NICU 80% vs PICU 69%) and no-CPR orders (NICU 20% vs PICU 30%)., Conclusions: This study confirms that both withdrawal of therapy and no-CPR orders are part of current clinical practice in both the NICU and PICU settings. The ethical foundations and implications of these practices need further elaboration.