There is a ton of research being performed as we continue to learn about COVID. Will address a few papers that have some practical implications. As always, the goal here is give you an appreciation for how the scientific community operates since they don’t get all the love they should.
We hear a lot about virus variants in the media along with the speculation that they may become “escape variants” and evade our immune response even if vaccinated or had COVID itself already. There is some preliminary data over the last few weeks that is likely to bolster that concern, though the studies have limitations that are significant and prevent drawing real conclusions at this time.
Hoffman, et al published in Cell findings that some isolated COVID strains were either not neutralized at all, or at a markedly diminished level by antibodies currently used to treat individuals infected with COVID. They further reported similar findings with sera from patients who recovered from COVID. This obviously raises serious concern as new strains are reported fairly frequently. This study however was not done using actual SARS-CoV2 virus, but rather vesicular stomatitis virus modified to present SARS-CoV2 capsid proteins. Furthermore, these modified viruses were used to infect immortalized cell lines, not primary tissue and this could also confound the results. In plain English, they used a dressed up virus to infect tissue that does not currently exist in the body as a proxy for true infection. Good enough for horseshoes and hand grenades. But just a starting point for everything else.
Stamatatos, et all published in Science findings that sera from individuals who recovered from COVID did not neutralize the B.1.351 variant to a significant degree. This study also demonstrated that a single dose of an mRNA COVID vaccine (Pfizer/Moderna variety of vaccine) administered in this same population of recovered individuals improved the ability to neutralize the B.1.351 strain. Conclusion: even if you had COVID, the vaccine may significantly boost your ability to respond to variants going forward.
It is very worth noting that these studies are addressing neutralization of virus only. They are also performing these studies in tissue culture. This is very different that measuring outcomes in a real live environment. First, our immune response is not limited to neutralizing antibodies. The mRNA vaccines also stimulate a T-cell response and these are not addressed by the studies above. Second, our titers of antibodies are able to rise with reinfection, so it is entirely possible that our bodies will ramp up production and overcome some limitations in neutralizing capability as a result. Third, ability to be infected and disease severity once infected are separate issues entirely. As mentioned earlier, the big study is ongoing……will our vaccinated population still get infected? Will they be protected from serious disease if they do get infected despite vaccination? Time will tell.
What these studies do raise as a caution is that escape variants could well emerge and that timely vaccination of the population is imperative to minimize their emergence. They also demonstrate that vaccination of those who already had COVID is likely to provide an additional level of protection.