Generally, the humoral immune system relies strongly on the production of specific antibodies for a successful immune response against a certain pathogen. An efficient immune response depends on certain factors, including the health and type of the pathogen, pathogenicity of the infection, and so on. New research indicates that three new, fast-spreading SARS-CoV-2 variants can evade antibodies that work against the original form of the virus that sparked the pandemic.

In general, a host can evolve two types of defense mechanisms to increase its fitness against a pathogen, resistance and tolerance. Resistance to external pathogens by the host immune system has been strongly debated by life scientists for many years. In humans, an alteration of toll-like receptor signalling is responsible for Plasmodium infection tolerance.

To date, we have seen that the SARS-CoV-2 virus is causing prominent harm to a certain group of people, such as those having diabetes, heart and lung diseases, and so on. However, the true groups that are resistant and/or tolerant to this detrimental virus are yet to be found out. 

It is evident that SARS-CoV-2 is always mutating. During winter, several fast-spreading variants of this virus were detected in the United Kingdom, South Africa, Brazil and elsewhere. It has been detected that these new variants carry multiple mutations in their spike genes. Now, there is a growing concern on the effectiveness of spike-targeted drugs, vaccines and antibody therapies used to prevent or treat this viral infection.

One study reports that the antibodies from the blood of SARS-CoV-2 recovered people vaccinated with the Pfizer vaccine neutralised the UK variant with a similar level, while the other two variants required from 3.5 to 10 times greater antibody levels for the neutralisation.

Although antibodies are not the only measure of host protection, the other elements of the immune system should be able to compensate for increased resistance to antibodies to fight against this dangerous virus. We may need to continually screen effective antibody levels as the SARS-CoV-2 variants arise and spreading to follow the success of the vaccines and antibody-treatment strategies.

The pandemic will claim thousands of lives before we find a true fighter (e.g., vaccine or drug). However, we should take additional measures along with the previously reported conventional measures (such as using hand sanitisers or handwashing, maintaining social distance, quarantine, etc.).