Canadian vaccine safety surveillance reports following immunization with seasonal influenza vaccines, 2021-2022.

Background: Seasonal influenza vaccines (SIV) authorized for use in Canada have all undergone rigorous regulatory assessments for safety and effectiveness. Serious adverse events following immunization (AEFI) can occur, though they are rare. Continuous safety surveillance of vaccines during the post-marketing phase is a critical component of vaccination programs. This enables the detection of rare, late onset, or unexpected adverse events. An updated safety summary following the introduction of any new vaccines and/or formulations to immunization programs is necessary for refining the risk-benefit profile of a specific vaccine and maintaining public confidence. Here we provide an updated safety summary for SIVs distributed during the 2021/2022 influenza season from AEFI reports submitted to the Canadian Adverse Event Following Immunization Surveillance System (CAEFISS) and the Canadian Vigilance Database (CVD). Methods: We searched CAEFISS and CVD for individuals who were vaccinated with a SIV between October 1, 2021, and March 31, 2022. Descriptive statistics were calculated, including median age of vaccinated individuals, vaccines co-administered with SIV, and the most frequently reported AEFIs. Crude AEFI reporting rates were calculated by severity of the AEFI report, and SIV-type using doses distributed data. Medical reviews were conducted for reports including death, serious events (or outcomes) after SIV were administered alone, and selected adverse events (i.e., anaphylaxis, Guillain-Barré syndrome, febrile seizures, oculo-respiratory syndrome). Disproportionality analysis was used to identify potential safety signals among SIV and AEFI pairs. Results: There were 448 AEFI reports, with most AEFI classified as non-serious events (84.2%). The majority of reports described vaccination in adults at least 65 years of age (38.6%). The most frequently reported AEFIs were vaccination site pain, urticaria, pyrexia and rash. Medical review of AEFI reports did not find any evidence that reported deaths were related to vaccination with SIV. Among serious reports, nervous system disorders were the most commonly reported medical conditions. A higher number of events related to vaccination errors were also identified using disproportionality analysis. Conclusion: Findings from our analysis of reports to CAEFISS and CVD following vaccination with SIV are consistent with the known safety profile of SIVs distributed during the 2021/2022 influenza season. The majority of reports were non-serious with the most common AEFI symptoms occurring at the vaccination site or systemic symptoms that were self-limiting. The majority of vaccination error reports involved the administration of the vaccine at an inappropriate site, although no serious AEFIs were reported.

A sub-national real-time epidemiological and vaccination database for the COVID-19 pandemic in Canada.

The COVID-19 pandemic has demonstrated the need for real-time, open-access epidemiological information to inform public health decision-making and outbreak control efforts. In Canada, authority for healthcare delivery primarily lies at the provincial and territorial level; however, at the outset of the pandemic no definitive pan-Canadian COVID-19 datasets were available. The COVID-19 Canada Open Data Working Group was created to fill this crucial data gap. As a team of volunteer contributors, we collect daily COVID-19 data from a variety of governmental and non-governmental sources and curate a line-list of cases and mortality for all provinces and territories of Canada, including information on location, age, sex, travel history, and exposure, where available. We also curate time series of COVID-19 recoveries, testing, and vaccine doses administered and distributed. Data are recorded systematically at a fine sub-national scale, which can be used to support robust understanding of COVID-19 hotspots. We continue to maintain this dataset, and an accompanying online dashboard, to provide a reliable pan-Canadian COVID-19 resource to researchers, journalists, and the general public.

A review of Cyclospora cayetanensis in animals.

Cyclosporiasis is a global, emerging disease in humans caused by Cyclospora cayetanensis. The role of animals in the epidemiology of cyclosporiasis is not fully understood. We conducted a narrative review of the published literature on C. cayetanensis in animals. MEDLINE® (Web of Science™ ), Agricola (ProQuest), CABI Global Health (1979 to December 2020) and Food Science and Technology Abstracts (EBSCOhost) (1979 to February 2020) were searched. Studies of C. cayetanensis in or on any species of animal were eligible. Thirteen relevant studies were found. C. cayetanensis was found in wild and farmed Mediterranean mussels (Mytilus galloprovincialis), wild grooved carpet shell clams (Ruditapes decussatus) and in the faeces of dogs (domestic and street), wild chickens, wild rhesus macaques (Macaca mulatta), chimpanzees (Pan troglodytes) from a wildlife research centre, and Cynomolgus monkeys (Macaca fascicularis) from an experimental primate research centre. As the small intestines of the naturally exposed animals were not biopsied, existence of a natural animal reservoir of C. cayetanensis could not be confirmed. Animals shedding oocysts in their faeces may be paratenic hosts. Investigators were able to successfully infect the following animals with C. cayetanensis: oysters, Asian freshwater clams (Corbicula fluminea), Swiss albino mice and guinea pigs. Future non-laboratory studies of animals should use PCR coupled with DNA sequencing to confirm that the species found is C. cayetanensis. The potential role of animals in the transport of oocysts and contamination of food, water, and soil could be explored through future primary research.