The search for an effective vaccine against all mutations in a virus is progressing

The quest for an effective vaccine against all mutations in a virus – a real grail of immunologists – is progressing. Moderna has announced that it is developing vaccines against several diseases at the same time.

Biotech firm Moderna said last Thursday start the study of a vaccine capable of fighting both influenza and COVID-19. A second study is also underway to test a vaccine against several strains of influenza virus. The company also published encouraging data in the development of a vaccine protecting against three different respiratory viruses.

If these trials are successful, they could give rise to a new generation of better performing influenza vaccines.

Scientists have been trying for years to develop such a so-called “universal” influenza vaccine. The traditional manufacturing process for these vaccines is so slow that, each year, specialists must “anticipate the mutations, changes or genetic deviations of the virus to try to have a vaccine that will be effective”, explains Dr. Maryse Guay, professor of public health at the University of Sherbrooke and specialist in vaccination programs. “There are years when we fall well, years when we fall less well. The effectiveness of these vaccines varies between 40% and 60%.

The World Health Organization estimates that influenza is responsible for about 3 to 5 million cases of serious illness each year, and 290,000 to 650,000 deaths.

Or, the messenger RNA technology that Moderna now uses is a “very malleable technology” which facilitates experiments, assures Dr. Cécile Tremblay, microbiologist-infectious disease specialist at the University of Montreal hospital center. Rather than using a disabled virus to craft the right recipe to include in the vaccine, this technology only needs the virus genome to fight.

To arrive at a universal vaccine, “we must target regions of the genome which are more conserved, and therefore which vary less, but which are common to all the variants,” explains Dr. Cécile Tremblay. “Usually it’s harder to do. “

What about COVID-19?

Dr. Cécile Tremblay recalls that the current vaccines against COVID-19 are already almost universal, because they “are still capable of eliciting the antibodies that will protect you against the severe disease of many variants”. The appearance of mutations escaping this protection nevertheless led him to conclude that “it could be optimized”.

The billions of dollars injected into the pharmaceutical industry since the start of the pandemic are certainly speeding up the process, she adds. “It will come quickly. […] [Les entreprises] are all working on it. “

Watch video