Billionaire Bill Gates wants to stimulate research to develop a universal and long-term flu vaccine.
One hundred years ago, the Spanish flu broke out. The pandemic, born in fact in the United States, would have killed at least 50 million, more than the fighting of the First World War. Since then, seasonal flu epidemics have tended to wreak havoc, killing between 290,000 and 650,000 people each year worldwide. A scourge against which Bill Gates decided to engage his philanthropic foundation, to encourage researchers to develop a universal vaccine against influenza.
"We believe that a universal flu vaccine could not only help eliminate pandemic risk, but also generate significant health benefits," Bill Gates told STAT magazine at a virtual conference. for doctors and public health experts. A demonstration of American-style optimism for which the Bill & Melinda Gates Foundation is committed to putting $ 12 million on the table.
A perverse and polymorphic virus
The viruses responsible for influenza (influenza) are very unstable, in addition to being highly contagious. Their genetic inheritance continues to evolve, by mutation or by recombination between subtypes, so that we never know which exact strain will strike. The new vaccines, designed each year with out-of-date strains, are therefore struggling, and the development of a universal vaccine represents a sort of epidemiological grail.
"I do not think we're close," said Professor Michael Osterholm, director of the University of Minnesota Infectiology Center, in the columns of STAT. "There has been crucial work, but we are only at the first meter when we need a thirty-meter rope."
Clinical trials by 2021?
Bill Gates' boost to the climbers will be in the form of individual scholarships ranging from $ 250,000 to $ 2 million over two years. For this tariff, scientists must be able to propose a prototype by 2021, valid and effective in animals, which protects against all subtypes of two major viruses, influenza A and B. Best of all, the immunity should last at least 3 to 5 years - against a few months for current vaccines.
The goal is therefore at least ambitious. The call for projects also invites scientists to use related fields, such as artificial intelligence, machine learning and bioinformatics. A bill, recently introduced in the US Senate, proposed to invest a billion dollars over five years. Given the budgetary priorities of the current administration, its chances of succeeding appear slim.
Ineffective vaccines ... but useful
Depending on the year, vaccination against influenza protects between 20 and 70% of vaccinated people. Despite these limited results, the Public Health Agency France estimates that vaccination avoids 2000 deaths per year in France among people over 65, while the virus is responsible for 9000 deaths per year in this country. category.
Current vaccines use a very unstable part of the virus, carrying antigens (haemagglutinins) capable of causing virulent immune responses, but very variable in their expression. One of the most advanced strategies being evaluated in humans is to target antigens in the "tail" of the virus (neuraminidases), which are less immunogenic but more stable.