What is causing the shift towards decreased mortality rates for COVID-19?
A dual phenomenon involving viral evolution towards milder disease and better-prepared population immune systems
The reduction in COVID-19 mortality is recognized as a combined effect resulting from two major ongoing processes. Firstly, the human population’s collective immunity, built up through both vaccination and prior infection, is maturing, meaning immune systems are significantly better prepared to neutralize severe outcomes upon encountering the virus. Secondly, the virus itself appears to be evolving within this immune landscape, potentially leading to strains that cause milder disease when they infect hosts whose immune systems are primed. This dual evolution—both in the pathogen and the host population's defense—is what drives the overall threat profile downwards, positioning the disease closer in severity to endemic respiratory diseases rather than its initial highly virulent state.
