A single-shot vaccine that protects against multiple coronaviruses, including the one that causes COVID-19, has been developed. It erased all viral traces from the lungs of animal subjects, opening a pathway for a similar human vaccine.
While Sars-CoV-2, the virus that causes COVID-19, has gobbled up most of the headlines these past few years, it's really just one nasty virus in a group of them. The class of bugs it belongs to is known as Sarbecovirus, which stands for SARS Betacoronavirus. These are viruses that mostly develop in bats and other mammals and have the potential to spread to humans like SARS-CoV-1 (which became commonly known as SARS during its 2020 outbreak).
As we all know by now, there are individual vaccines to combat different viruses like the ones that ward off COVID-19 and the flu. But getting people to take multiple vaccines is a challenge. Plus, it gets even trickier because these vaccines need to be repeated on a regular basis for them to have maximum efficiency.
In what could be a step change in the fight against coronaviruses, researchers at the Georgia Institute of Technology and the University of Wisconsin-Madison created a new vaccine that, when tested on hamsters, removed all traces of SARS-CoV-1 and SARS-CoV-2 plus its omicron variants from the animals' lungs. The team had previously identified hamsters as suitable animals on which to test potential vaccines.
Spiking the virus
To create the vaccine, the team focused on the same thing that the anti-COVID mRNA vaccines targeted: the spike proteins that are a hallmark of coronaviruses. In this case, the researchers created a trivalent vaccine, meaning that it targets three prominent spike proteins common to multiple Sarbecoviruses, particularly variants of the SARS and COVID-19 causing bugs.
The researchers say that they are hopeful that their successful vaccine can be further developed to combat germs from other coronavirus subfamilies as well as other viruses like those that cause the flu. They indicate the desire for some of the specific antigens they developed in their research to move forward to preclinical trials and they imagine what other types of research could help expand and improve their findings.
"While we are encouraged by these results, there are several additional avenues that would be interesting to explore in future work," they wrote in a paper published in Nature Communications. "Enhancing mucosal immunity might not only enhance protection against viral infection, but also decrease viral transmission. Intranasal vaccination against SARS-CoV-2 has been explored with several platforms (and) the adaptation of our platform for intranasal delivery could be a promising avenue for improving the mucosal response. Characterizing the longevity of protection would also be an interesting avenue for future research. It would be particularly interesting to determine whether stronger mucosal immunity results in more durable protection against symptomatic disease."
Based on the results of the future research projects they detail, a trivalent sniff once every few years rather than multiple jabs in the arm every year may eventually become the standard of care for boosting our defenses against multiple infections.
Source: Georgia Tech
