A Qatar Study Says It All About Natural Immunity
On the durability of natural immunity
In many ways, this is old news. If you’ve been paying attention to Covid science, natural immunity lasts longer. But it is interesting to see the way this scientific study out of Qatar lays out natural immunity:
Protection of natural infection waned with time after primary infection, prior to Omicron emergence, and reached ∼70% by the 16th month. This waning likely reflects genuine waning in biological immunity rather than viral immune evasion, as pre-Omicron variants demonstrated much less immune evasion than Omicron. This waning in natural immunity mirrors that of vaccine immunity, but at a slower rate. Vaccine immunity may last for only a year, but natural immunity, assuming Gompertz decay, may last for 3 years, as also suggested by long- term follow-up of SARS-CoV-1-associated antibodies, and incidentally not dissimilar to pandemic-influenza-associated antibodies.
Despite waning protection against reinfection, strikingly, there was no evidence for waning of protection against severe COVID-19 at reinfection. This remained ∼100%, even 14 months after the primary infection, with no appreciable effect for Omicron immune evasion in reducing it.
That’s 14 months. Maybe, just maybe, mother nature can do things better than snobs in white coats.