News release

From: The Royal Society

COVID-19 hospitalisation rates rise exponentially with age, inversely proportional to thymic T-cell production

COVID-19 hospitalisation rates follow an exponential relationship with age, doubling for every 16 years of age or equivalently increasing by 4.5% per year of life. This mirrors the well studied exponential decline of T-cell production, which halves every 16 years. COVID-19 can therefore be added to the list of other diseases with this property, including those caused by MRSA, MERS-CoV, West Nile virus, Streptococcus Pneumonia and certain cancers. Risk is also higher in men, consistent with the degree to which thymic involution (and the decrease in T-cell production with age) is more severe in men compared to women. 

Exponential COVID risk - The risk of COVID-19 hospitalisation increases exponentially with age, equivalent to a 4.5% increase per year of life. UK researchers found the rise mirrors an exponential reduction in the immune system’s T-cell production. There was no evidence for differences in susceptibility to infection or infectiousness with age.