Immune system & COVID-19 18.9.22: https://theconversation.com/ive-had-covid-and-am-constantly-getting-colds-did-covid-harm-my-immune-system-am-i-now-at-risk-of-other-infectious-diseases-188899 19,8.22: https://www.medscape.com/viewarticle/979521 22.6.2022: https://onlinelibrary.wiley.com/doi/10.1111/imr.13089 15.5.2022: https://businesstech.co.za/news/trending/586586/how-omicron-infection-turbo-charges-vaccinated-peoples-immunity/ 12.5.2022: https://www.news-medical.net/news/20220512/Study-finds-recent-influenza-vaccination-is-associated-with-an-appreciable-reduction-in-the-risk-of-SARS-CoV-2-infection-and-COVID-19-severity.aspx https://www.medscape.com/viewarticle/972647 28.2.2022 https://www.weforum.org/agenda/2022/02/study-regular-exercise-can-prevent-death-from-covid-19-by-up-to-42/ 21.4.2021 https://theconversation.com/exercise-boosts-immunity-and-makes-vaccines-more-effective-new-study-159248 Population Immunity and Covid-19 Severity with Omicron Variant in South Africa nejmoa 24.2.2022.pdfDownload Novel antibody helps block COVID transmission in cells, finds study