There were 98.1% of Canadian adults who had COVID-19 antibodies from April to August, according to data released by Statistics Canada. .Over this period, 53.9% of Canadians living in private dwellings had antibodies indicating a past infection, which is more than 20 times higher than the 2.6% observed from November 2020 to April 2021, according to the Monday data. These antibodies were acquired through vaccination, a previous infection, or a combination. .The data said some people who had COVID-19 antibodies from a past infection were unaware they had it. Among Canadian adults in summer 2022 who had a past infection, it said 47.9% had tested positive for it at least once. .One-tenth with antibodies from infection suspected they had contracted it but never tested positive. On the other hand, 41.7% of Canadians with antibodies from a past infection never tested positive or suspected an infection. .Self-administered rapid antigen tests (RATs) became the main way Canadians tested positive for COVID-19 in 2022. Three-fifths of people with antibodies from a past infection with a positive result obtained it from a RAT, while two-fifths received one from a PCR test. .The data went on to say 88.3% of Canadians who had tested positive for the virus had antibodies from a past infection. It said 56.4% of those who suspected an infection had them, and 36.9% of those who never tested or suspected contained them. .Levels of antibodies against a COVID-19 infection were higher from 14 to 90 days after an infection (89.9%), and this percentage decreased over time. While this is indicative of decreasing antibodies, there are a number of factors impacting this analysis. .Since vaccines can lead to a lesser antibody response following an infection, the percentage of Canadians with them might be affected by changing vaccination rates over time. Since the data focused on first infections, reinfections would impact the analysis, as these could lead to a rebound in antibody levels. .Public health authorities provided guidance throughout the COVID-19 pandemic to reduce the spread of the virus. Due to factors such as living with others or needing to go into school or work, select people were limited in their ability to avoid exposure to the virus. .The data said Canadians living with a chronic symptom, condition, or cancer were less likely (51.7%) than those without one (58.5%) to have antibodies from a past infection. It added seroprevalence decreased as the number of chronic conditions increased. .Nonwhite Canadians (60.1%) were most likely to have antibodies from infection compared to white people (51.8%). Chinese Canadians (53.2%) had lower rates of antibodies from infection compared with blacks (80.7%), Arabs (78.1%), Filipinos (69.8%), and Latin Americans (64.6%). .The data continued by saying seroprevalence varied by province. It said Nova Scotia (46.5%) had the lowest amount, but Alberta and Saskatchewan (57.4%) were the highest. .Numbers were similar for women (53.4%) and men (54.3%). .A Qatari study published in July reported prior infection with any COVID-19 variant provides those newly infected with high levels of natural immunity. .READ MORE: Large study says innate immunity naturally effective against severe COVID.“Effectiveness of primary infection against severe, critical, or fatal COVID-19 reinfection was 97.3%, irrespective of the variant of primary infection or reinfection, and with no evidence for waning,” said study co-author Laith Abu-Raddad. .“Similar results were found in sub-group analyses for those less than 50 years of age.” .The data saw Statistics Canada collect dried blood samples (DBS) to identify COVID-19 antibodies from April 1 to August 31, with a small number collected until October 17. Estimates of seroprevalence are based on participants who completed the DBS sample collection between April and August 2022.
