Unraveling a pandemic: from avian to swine influenza

Ruy M. Ribeiro

Influenza is a viral infection that affects millions of people every year in the USA, with up to thirty thousand people dying from its complications. We often think of it as a mild disease, however in recent years much has been said about the “fear of a pandemic” of influenza. Indeed, we are in the midst of a pandemic declared by the World Health Organization on June 11th 2009, due to a novel H1N1 virus. At the same time, there continues to be a steady stream of cases of highly pathogenic H5N1 virus in Southeast Asia.

But exactly what is the influenza virus? What is the meaning of those H1 vs. H5? How does it cause disease? What do epidemics look like and how do we control them? There have been innumerous studies looking at these questions from the molecular to the epidemiological level (including important efforts at LANL), and I will discuss the main points relevant to understanding this infection. Still, we do not know exactly why some strains are more pathogenic than others or more transmissible than others, I will also talk about our knowledge gaps in this area.