Published: January 4, 2010
Evolution is a virus’s secret weapon. The virus can rapidly slip on new disguises to evade our immune systems, and it can become resistant to antiviral drugs.
But some scientists are turning the virus’s secret weapon against it. They hope to cure infections by forcing viruses to evolve their way to extinction.
Viruses can evolve because of the mistakes they make when they replicate. All living things can mutate, but viruses are especially prone to these genetic errors. In fact, some species of viruses mutate hundreds of thousands of times faster than we do.
Many of the mutations that strike new viruses are fatal. Others only slow down their growth, and still others have no effect at all. A few mutations are beneficial, and the viruses that inherit those good mutations can swiftly dominate a viral population.
Viruses depend on this rapid evolution to infect a host successfully. Poliovirus, for example, enters the body in the gut and then moves into the bloodstream, muscles and, in a small fraction of cases, the nervous system.