Silk Summary:
Natural Immunity Protects Against Severe Infection Throughout Pandemic
Study Indicates Prior Infection, Milder Strains were Protective while Vaccination Backfired and Increased Risk of Hospitalization
When a patient called from from 2022 forward with a new episode of COVID-19, the first thing I asked them was “have you had COVID-19 in the past?” This is such an important question because that natural immunity has been powerful in mitigating risks of future COVID-19 hospitalization.
Uuskula et al […]
leveraged a nationwide database in Estonia to give critical information on the changing waves of COVID-19 infection:
“Vaccination in Estonia began in January 2021, with a cumulative vaccination uptake about 70% among adult population by June 2022. Within the time period of data underlying the present study, Estonia had three large pandemic waves: the first was from March to June 2020 (SARS-CoV-2 pre-variant of concern era); the second was from November 2020 to May 2021 (first the Alpha variant, then the Delta variant); and the third was from December 2022 (Omicron variant). Our analysis used data derived from the nationwide and population-based universal tax-funded Estonian health care system. We conducted a retrospective cohort study (N=329,496 adults which allowed 246,113 individuals being matched into the three cohorts) based on linking individual-level data on laboratory-confirmed COVID-19, SARS-CoV-2 vaccination status, and health care utilization between 26 February 2020 and 23 February 2022 from the national e-health records.”