June 27, 2017
Evolution is usually very slow, a process of change that takes thousands or millions of years to see.
But for influenza, evolution is fast – and deadly. Flu viruses change rapidly to escape the body’s defenses. Every few years, new variants of flu emerge and cause epidemics around the world.
Controlling the spread of flu means dealing with this ongoing evolution. Each year, experts from the World Health Organization (WHO) must make their best guess about how the virus will change in order to choose which flu strains to include in the annual vaccine.
This work is difficult and uncertain, and mistakes have real consequences. Worldwide, flu infects several million people each year and causes hundreds of thousands of deaths. In years when predictions miss the mark and the flu shot is very different from circulating strains, more people are vulnerable to infection.
In the past several years, advances in genome sequencing have begun to shed light on the beginnings of viral evolution, deep within individual infections. We wondered whether, for flu, this information might give us an early glimpse of future global evolutionary trends.
What could a single person’s flu infection tell us about how the virus changes across the world? As it turns out, a surprising amount.
The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.