14 DAY TRIAL // Researchers from the University of Cambridge and the Erasmus Medical Center, in the Netherlands, say that new types of flu vaccines may be right around the corner. In a new study, the team determined that the flu virus bypasses immunity by very simple changes in its structure.
The work revealed that single amino-acid substitutions allow the pathogen to render vaccines developed during the previous flu season useless. The team also found that these substitutions only occur at seven locations on the virus' surface, not 130, as previously determined.
Now that these areas have been accurately identified, it may be possible to develop vaccines that cover any of the possible amino acid permutations, essentially preventing the viral agent from escaping immunity every again. Details of the work appear in the November 21 issue of the top journal Science.
This investigation was led by Cambridge professor Derek Smith and Erasmus professor Ron Fouchier. They say that current flu vaccines work by exposing the immune system to three major strains of the virus. This allows our natural defense systems to create antibodies that fight off infection.
But when changes occur on the outer surface of the viral agent, the antibodies in our blood system become unable to recognize the virus, and are therefore not activated. The virus is thus allowed to run free through our bodies, and infect us again. All this may soon be history thanks to the new study.
“This work is a major step forward in our understanding of the evolution of flu viruses, and could possibly enable us to predict that evolution. If we can do that, then we can make flu vaccines that would be even more effective than the current vaccine,” Smith explains.
Previously, virologists believes that the flu virus had to produce at least four amino acid substitutions in order to escape immunity. The research determined that a single substitution is enough for this job. In a series of experiments, the group checked all possible substitutions and combinations of substitutions.
Even though it is very common, the flu virus is still able to kill in excess of 500,000 people around the world every year, while millions of others require hospitalization due to severe responses to infection.