The risk of COVID-19 also varied by the number of COVID-19 vaccine doses previously received. The higher the number of vaccines previously received, the higher the risk of covid infection. Download free high-res PDFs of the posters, download free copies of my two text books. Any donations using this link help the work of campbell teaching. https://drjohncampbell.co.uk/ Order a hard copy Physiology book in the UK, https://www.ebay.co.uk/itm/1549733923… Vaccine doses versus risk of covid during the 3-month study period One dose, 1.7 times more likely to test positive for covid Two doses, 2.63 times more likely to test positive for covid Three doses, 3.1 times more likely to test positive for covid More than three doses, 3.8 times more likely to test positive for covid So compared to the unvaccinated 1, x 1.7 2, x 2.36 3, x 3.1 4, x 3.38 P = 0.001 means 999 out of 1,000 likely to be a genuine result That 99.9% likely to be a genuine result Effectiveness of the Coronavirus Disease 2019 (COVID-19) Bivalent Vaccine https://www.medrxiv.org/content/10.11… In 2020 (published in 2021) Evidence that vaccines prevented covid infection https://www.medrxiv.org/content/10.11… This was when the human population had just encountered the novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virus Things Have Changed (Dylan) Bivalent antigens Original vaccine and BA.4/BA.5 lineages of Omicron. (Approved without demonstration of effectiveness in human clinical studies) (Approved without demonstration of safety in human clinical studies) Background To evaluate whether a bivalent COVID-19 vaccine protects against COVID-19. Methods Employees of Cleveland Clinic, n = 51,011 Cumulative incidence of COVID-19 was examined over the following weeks. Protection provided by recent and prior vaccination was evaluated First bivalents given, 12 September 2022 Three-month study Results Among 51,011 employees, 20,689 (41%) had had a previous documented episode of COVID-19, 42,064 (83%) had received at least two doses of a vaccine. 10,804 (21%) were bivalent vaccine boosted COVID-19 occurred in 2,452 (5%) during the study. (Pfizer 89%, Moderna 11%) Risk of COVID-19 increased with time since the most recent prior COVID-19 episode Risk of COVID-19 increased with the number of vaccine doses previously received. Note, this is based on large numbers Doses, 0 = 6,419 (12.6%) Doses, 1 = 2,528 (5%) Doses, 2 = 14,810 (45.9%) Doses, 3 = 23,396 (45.9%) Doses 4, 3,757 (7.4%) Doses 5, 85 (less than1%) Doses 6, 16 (less than 1%) The bivalent vaccinated state Was independently associated with lower risk of COVID-19 (HR, 0.70) (over the 3 months of the study) Leading to an estimated vaccine effectiveness (VE) of 30% CDCs latest variant data https://covid.cdc.gov/covid-data-trac… Things Have Changed (Dylan)