All known flu strains could potentially be contained by a new vaccine based on mRNA technology, first widely used during COVID-19.
The multi-vaccine was developed by scientists at the University of Pennsylvania in the US, who tested it on mice, among other things. The rodents became less sick and did not die when exposed to common virus strains other than those contained in the vaccines.
“The idea is a vaccine that gives people a baseline level of immune memory against different strains of flu so that there are far fewer sick and dead people when the next flu pandemic hits,” said Scott Hensley, a professor of microbiology at the university’s medical site.
That’s how the vaccine works
The researchers developed a type of antigen that elicits immune responses against 20 known flu strains and subforms.
Using mRNA technology, a genetic code is delivered to the cells with a faithful copy of the flu in two injections.
The code snippet with the messenger in the RNA vaccine, it gives the cells a recipe for the basic properties of the 20 known flu strains and causes the body to produce the protein hemagglutinin, which spreads the harmless ‘flu recipes’ around your cells.
When the immune system detects a flu copy, it prepares to fight the simulated virus.
The immune system is then equipped to recognize a real flu virus and fight it off with antibodies when it enters the body.
Pandemics can be contained
The World Health Organization estimates that around 650,000 people die each year from seasonal flu. The Spanish flu killed at least 50 million people between 1918 and 1920, while corona has so far killed just over 6.6 million people.
The researchers emphasize that their new vaccine can relatively easily recognize the immune response and adapt to new flu variants, significantly reducing the impact of emerging pandemics.
However, they also point out that the vaccine is not flawless. The effect will be similar to the first generation of mRNA corona vaccines, targeting the original Wuhan strain.
‘In later variants, such as omikron, these original vaccines did not completely block viral infections, but they continue to provide lasting protection against serious illness and death,’ says Professor Scott Hensley, one of the scientists.
People are next step
He and his team are now preparing the next steps in the development of the vaccine: human clinical trials.
According to the researchers, if this step is successful, it is likely that everyone, including children and the elderly, can be vaccinated against known flu strains and thus train their immune system to deal with unknown strains of flu as well.
Pharmaceutical companies such as Pfizer and Moderna are already conducting such human trials, but according to the Reuters news agency, these are “only” vaccines against the last four major flu strains.
In several countries, researchers are looking for subjects for Moderna’s multi-vaccine, which will be tested for efficacy and safety in 23,000 mostly older people worldwide.