Factoid:
Most influenzas actually originate in birds, then the virus has to mutate to infect a mammal, and then evolve again to get from a mammal to a human. - Dr. Marilyn Roossink, virologist, Noble Foundation.
Factoid:
Most influenzas actually originate in birds, then the virus has to mutate to infect a mammal, and then evolve again to get from a mammal to a human. - Dr. Marilyn Roossink, virologist, Noble Foundation.