© Reuters. FILE PHOTO: People enter a store near a sign promoting a flu shot in New York January 10, 2013. REUTERS/Andrew Kelly/File Photo
By Nancy Lapid
(Reuters) – An experimental vaccine provided broad protection against all 20 known influenza A and B viruses in preliminary tests on mice and ferrets, potentially paving the way for a flu shot that could help prevent future outbreaks, according to a U.S. study published today. Thursday.
The two-dose vaccine uses the same messenger RNA (mRNA) technology used in the COVID-19 vaccine developed by Pfizer (NYSE: ) and BioNTech, and Modern (NASDAQ:). They provide lipid particles containing mRNA instructions for cells to produce copies of the hemagglutinin protein that appears on the surface of the influenza virus.
Universal vaccination may not mean the end of flu seasons, but it could replace the hypothetical program that produces annual shots months before the flu season each year.
“The idea here is to have a vaccine that will give people an early immune response to different types of flu, so that there will be less illness and death in the next flu pandemic,” lead researcher Scott Hensley of the Perelman School. of Medicine at the University of Pennsylvania said in a statement.
Unlike the flu vaccine that provides one or two types of hemagglutinin, the experimental vaccine includes 20 different types in the hope of getting the immune system to recognize any flu virus it encounters in the future.
In the new lab, the immune system of vaccinated animals identified hemagglutinin protein and protected against 18 different types of influenza A and two types of influenza B. Antibody levels due to vaccination remained unchanged for four months, according to a report published in the journal Science.
The vaccine reduced disease symptoms and protected against death even when the ferrets were exposed to a strain of flu not in the vaccine, the researchers said.
Moderna and Pfizer both have mRNA flu vaccines in early human trials, and GSK and partner CureVac are testing mRNA flu vaccines in early human safety trials. These vaccines are designed to protect against only four types of flu that have recently been circulating, but they say they can be changed every year.
A universal flu vaccine, if successful in human trials, would not prevent infection. The goal is to provide permanent protection against serious illness and death, Hensley said.
Questions remain about how to judge the effectiveness and utility of vaccines against emerging viruses that are not currently circulating, Alyson Kelvin and Darryl Falzarano of the University of Saskatchewan, Canada, wrote in a review published by the study.
Although promising results with the new vaccine “show the ability to protect against all types of influenza viruses, we cannot be sure until clinical trials in volunteers are completed,” said Adolfo García-Sastrem, director of the Institute for Global Health and Emerging Pathogens at Mount. Sinai Hospital in New York, he said in a statement.