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 10 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 with many other unfortunate victims, I did all right – and I am very grateful for the care I received.
Now, as the surge in cases takes new life, I will be on the front lines 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 have the same question faced by millions of others: Am I safe now?
It is no surprise that studies have shown health care workers comprising 6% of COVID hospital admissions, with one-third of these admissions being nurses. Recently, we heard that over 900 health care 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 rerun? 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.
Innate and adaptive 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-cell–mediated immunity that should protect one against a second infection with the same agent.
What about herd immunity?
Herd immunity is defined as essentially yielding to the virus and letting it spread naturally in order to develop community-wide immunity. By consequence of a large proportion of the population becoming immune after exposure to the disease, person-to-person spread can potentially be mitigated. This does not confer immunity to the virus at the individual level; rather, it reduces the risk of vulnerable people coming in contact with the pathogen.
Unfortunately, depending on herd immunity as a way to deal with COVID-19 has not worked well, even in well-contained countries like Sweden, where a disproportionate number of their most vulnerable populations have died. It is self-evident that containment strategies with vaccination may be our best way forward to achieve herd immunity. Not surrendering to the virus.