Baltimore, Maryland - Small sample, big hope: that's about the best way to describe a new study on immune response coronavirus mutations.

A landmark study carried out by researchers from the US National Institute of Health at Johns Hopkins University, in cooperation with the Singapore-based company ImmunoScape, brings great news as the second year of the pandemic gets underway.

The motivation behind this study was the concern that current vaccines or a previous Covid-19 infection may not protect against re-infection with newer variants emerging from South Africa and Brazil.

According to the Daily Mail, the researchers had initially found that the antibodies targeting the original version of the coronavirus did not work as well with the newer, mutated strains of the virus. These are the same type of antibodies produced by vaccination.

They then shifted their focus from antibodies to "T cells", which are a type of white blood cell that direct the body's immune response to a pathogen.

And the preliminary results are a reason for cautious optimism: the scientist found that "virtually all" T cells should "recognise these newly described variants".

T cells are part of the immune system and watch for invading viruses or bacteria. They are always on the lookout for a specific bug to attack – in this case, the coronavirus that causes Covid-19.

When the T cells find the virus, they can destroy other cells infected with it and signal the immune system to send out marked proteins called antibodies to bind to invaders, and mark them for the immune system to fight.

In the researchers' study, blood samples from 30 people who had recovered from Covid-19 were mixed with different strains of the coronavirus, and the researchers saw immune responses in all of them.

Although the responses were fairly weak and may not be strong enough to completely stop the coronavirus, they would likely still prevent serious illness or death.

The findings suggest that all licensed vaccines should be able to provide some degree of protection. Even a previous Covid-19 infection could prove beneficial to a point. As new variations would then no longer able to cause such severe symptoms in immunized people, there would be far less reason to fear them.

The hope for many is that the vaccines could still be adapted, potentially bringing a quicker end to the pandemic. The study was published on 30 March in the journal Open Forum Infectious Diseases.