Q&A – Natural Immunity vs COVID-19 Vaccines Part 2
Bottom Line: A CDC study of 492 adults in Kentucky who’d previously had COVID-19, found those who were vaccinated after recovering from the infection were 2.34 times less likely of becoming re-infected with the virus as opposed to those who relied on natural immunity alone. So, if reinfections from natural immunity are rare, reinfections with the combination of natural immunity and a vaccination are likely near-nonexistent at this point. This study is the most recent basis under which the CDC recommends those who’ve recovered from COVID-19 still seek a vaccination.
The challenge with getting more specific information boils down to reporting. While vaccination status is stored by the state, and thus breakthrough cases are documented, there’s not information collected and aggregated by the states regarding reinfections – at least not that’s made publicly available if it does exist somewhere. The most comprehensive study on reinfection was conducted in Denmark with the results published in the medical journal The Lancet earlier this year. In the study, 0.65% of those who’d contracted COVID-19 and recovered, contracted it a second time within a year. In the study they noted the rate of reinfection rose with age with those over 65 most susceptible to reinfection. That gives us a baseline to consider, however the study was before the advent of the variants, so it’s unclear exactly where we stand other than the CDC’s guidance that reinfection is “rare”.
Regarding the total number of Americans and Floridians with natural immunity, that we do know. Nationally 32,503,995 Americans, or right at 10%, of the US population has fully recovered from COVID-19 and thus has natural immunity. In Florida, 2,447,654 or about 11.4% of the state’s population, have fully recovered with natural immunity. Based on the available data, its evident natural immunity is most effective at combating COVID-19, followed by the vaccines, though there’s also evidence vaccinations on top of natural immunity is most effective. Hopefully that’s helpful.