Covid jabs may work against future viruses, study suggests
THE Pfizer and Moderna vaccines point the way to conquering the next coronavirus pandemic and may already offer some basic protection against viruses such as Mers or other as yet undiscovered threats.
In a study described by leading scientists as “exciting”, researchers at Duke University tested mRNA vaccines similar to the approved jabs on monkeys.
The vaccines induced antibodies that not only protected against Sars-CoV-2, the virus that causes Covid-19, but could also guard against other viruses from the same family, they found.
“These results demonstrate current mRNA vaccines may provide some protection from future zoonotic betacoronavirus [animal-to-human] outbreaks, and provide a platform for further development of pan-betacoronavirus vaccines,” the paper, published this week in Nature, concludes.
Sars-Cov-2 is the third threatening coronavirus to arise this century, after the viruses causing Mers (Middle East respiratory syndrome) and Sars (Severe acute respiratory syndrome), and experts agree that another could easily take hold.
The team at Duke Human Vaccine Institute, led by Prof Kevin Saunders, also tested a new vaccine they have developed. It is a protein nanoparticle vaccine, which works slightly differently to the existing mRNA vaccines.
It showed even more potent crossprotection against other coronaviruses, including all known variants of SarsCoV-2, bat coronaviruses and SarsCoV-1, which causes Sars. This new vaccine also stopped viral replication in the nose, suggesting it could have a major impact on transmission.
The new vaccine works by targeting a particular part of the virus, the receptor binding domain (RBD), which is a critical part of the spike protein that allows the virus to enter human cells.
It is also a part of the virus which is very stable between the different variants, or even between entirely different coronaviruses, which is why it appears to generate these “broadly neutralising antibodies” that could stop emerging pandemics in their tracks. The reason that the Pfizer and Moderna jabs might work similarly, in terms of the antibody response at least, is that they target the entire spike protein of Sars-Cov-2, which includes the RBD.
Prof Saunders told The Sunday Telegraph: “We found that the nanoparticle vaccine generated a really potent antibody response against these different viruses. And we found that even if you get an mRNA vaccine, similar to what Pfizer and Moderna have made, your body will generate a similar type of response, but it is weaker.”
The question now is how strong that response needs to be in order to provide protection, and whether the results in monkeys can be replicated in humans.