The 12+ million people in the US, and 60 million worldwide, who have been infected with COVID-19 — and survived — are likely asking themselves the same questions: am I immune now? Is it over or do I have to brace myself for the possibility of a reinfection? Moreover, could the second time potentially be worse than the first?
I was diagnosed with COVID in March of this year. After spending ten days in the hospital, and one night in the ICU, it took another 2 months for the air-hunger, headaches and fatigue to completely resolve. Compared to many other unfortunate victims, I did alright — and I am very grateful for the care I received. Now, as the surge in cases takes new life, I will be on the frontlines taking care of patients. Having had an eventful personal encounter with the virus, I now have a unique vantage point and remain fully committed to paying my fortunate circumstances forward. Although I can’t help but wonder about the same question faced by millions of others: am I safe now?
It is no surprise that studies have shown healthcare workers comprising 6% of COVID hospital admissions, with one-third of these admissions being nurses. Recently, we heard that over 900 healthcare workers at Mayo Clinic had acquired the infection in the first 2 weeks of the ongoing second COVID surge. Are these frontline workers protected? Can they return to work with no fear of a re-run? Or for that matter anyone who has been afflicted by COVID, are they now forever immune?
There are no clear answers here. But to understand this a little, let’s quickly revisit some basic principles of immunity.
Simply put, there are two forms of immunity: innate and adaptive. Innate immunity encompasses our body’s natural protective mechanisms that come into play almost immediately. This enables recognition of the virus and activates an immediate antiviral defense and attempt at removal of the infective agent. This, however, does not always do the job. Accordingly, a couple weeks after the initial exposure to the pathogen, adaptive immunity is invoked. Circulating white blood cells within our body recognize the virus and set off an immune response, involving the activation of T and B cells that actively attack the infective agent. It is this T and B…