Recently, a team of scientists from Germany and Britain improved methods used to determine which strains of the flu virus to include in the current season’s vaccine. Getting a vaccine might help prevent people from falling sick during flu season. But the vaccines only work if the virus strain that is likely to be active is accurately predicted by the vaccine developers.
“Seasonal influenza kills about half a million people per year, but improved vaccines can curb this number,” said Michael Lassig, study author from the Institute for Theoretical Physics, University of Cologne, Koln, Germany, the journal GENETICS reported.
“Although this study is some distance from direct applications, it is a necessary step toward improved prediction methods. We hope that it helps yield better vaccines against influenza,” Lassig added, according to a Cologne statement.
To make this advance, scientists analysed the DNA sequences of thousands of flu strains isolated from patients worldwide, dating to 1968. By analysing this dataset, researchers were able to determine which strains were most successful at expanding into the entire population, and which mutations were least successful in spreading.
Using a new statistical tool, researchers found that many more mutations than we thought initially succeed in replicating and surviving. These mutations compete; some make it into the entire population, others die out.
This analysis of the virus enables the prediction of trends which can help vaccine developers understand the rules of flu virus evolution. This knowledge, in turn, can be used to predict which strains of the virus are most likely to spread through a human population.