Getting a vaccine against all subtypes is one of the biggest global health goals, as it is difficult to anticipate each year which strain will cause the next pandemic.
A team of American scientists has successfully tested a prototype of a mRNA vaccine that contains germs of the 20 known subtypes of influenza viruses A and B and that could serve as the basis for a universal vaccine.
According to an article published in the journal Science on Thursday, the vaccine produced high levels of results achieved and specific for each subtype in mice and ferrets, and customize to protect animals against disease symptoms and death following infection with influenza strains.
Getting a universal flu vaccine is one of the major global health goalssince it is difficult to anticipate each year which flu strain will cause the next pandemic.
Only in Spain, in 2020, this virus, which is especially serious in those over 64 years of age and in risk groups, causing more than 600,000 cases, 1,800 ICU admissions and 3,900 deaths, according to the Carlos III Health Institute.
Vaccine that attacks all subtypes
Unlike other prototypes that contain a reduced set of hypertensives shared between virus subtypes, this vaccine includes specific resistances of each subtype.
Inspired by the success of RNA vaccines against SARS-CoV-2, the team led by Claudia Arévalo, from the University of Pennsylvania, prepared 20 different mRNAs encapsulated in nanoparticles, the same technology used by Moderna to develop its vaccines against SARS-CoV-2. coronavirus.
Each of the RNA encoded a different hemagglutinin boostera highly immunogenic flu protein that helps the virus enter cells, the study says.
The educational levels remained almost stable four months after vaccination in mice.
Multivalent protein vaccines produced using more traditional methods elicited fewer trials and were less protective compared with the multivalent mRNA vaccine in animals, according to the study.
For Adolfo García-Sastre, director of the Institute for Global Health and Emerging Pathogens at Mount Sinai Hospital in New York and author of several patents for flu vaccines in clinical development, the study is «very interesting», according to statements collected by Science. Media Center (SMC).
The study «demonstrates the ability to develop multivalent mRNA vaccines that are capable of immunizing at the same time against 20 or perhaps more sensitive to the different. In this case, they are captured from influenza viruses that encompass all possible subtypes and variants of the influenza virus, including those with pandemic potential.»
Current flu vaccines do not protect against virus with pandemic potentialbut this vaccine, «if it works well in people, would achieve this«.
In any case, despite being a very promising preclinical study that suggests a protective capacity against all subtypes of influenza viruses, «we cannot be sure of this until clinical trials are carried out on volunteers,» concludes the Spanish researcher.
In addition, in a related «Perspective» published in Science, Alyson Kelvin and Darryl Falzarano of the University of Saskatchewan, Canada, warn that «questions remain about the regulation and approval pathway for such a vaccine that is being targets viruses with pandemic potential but not currently in human circulation.