Swine flu inaccurate moniker; CDC identifies 3 strains in H1N1 virus

ATLANTA Last week, the Centers for Disease Control and Prevention and the World Health Organization renamed what had become known as the “swine flu” to H1N1 in part because sequencing results of the virus was found to contain genetic reassortment of three viruses which have been circulating in pigs in Europe, Asia and America since 1998.

The new information suggests that the progenitor virus strain was a virus circulating in swine and has evolved in humans through gradual mutations over a 10-12 year span, and has avian and human components.

The new information also provides other insight into influenza virus strains, such as the fact that influenza viruses, whether in humans or among animals, are constantly evolving genetically, along with changes in their ability to cause morbidity and mortality in humans or animals. These changes may be gradual or very rapid.