The Fear of the Known
Publishing the genetic sequence of a transmissible influenza virus might be scary, but harder decisions are yet to come
What Causes Epidemics?
Viral outbreaks are by definition the result of the interplay among virus, host and a variety of environmental, demographic and social factors. As a result, we cannot really say that the 1918 genome explains the pandemic any more than we can say that the murder of Archduke Ferdinand, by triggering the war, accounts for the pandemic. Unquestionably, certain strains of influenza are more dangerous than others: The 1918 strain made people far from the trenches in Belgium and France very ill. But the fate of even the most virulent of strains is not written solely in its genes.
In all likelihood, enough has changed over the past several decades that the 1918 strain would no longer cause a worldwide pandemic were it released today. Today’s population has been exposed to related (but less harmful) influenza strains, providing a measure of immunity. Further immunity derives from the nearly 450 million doses of flu vaccine administered worldwide annually. The advent of antibiotics would significantly reduce the development of secondary infections, one of the leading causes of influenza-related mortality in 1918. These and other changes in the overall health and nutritional status of the human population have altered the landscape of potential epidemics in radical ways. This is in no way meant to suggest that the human population in its current status is not fertile soil for pandemics. As recent experiences with severe acute respiratory syndrome (SARS) and H5N1 influenza suggest, emerging infectious diseases are constantly smoldering beneath the surface, just waiting to break out into full-fledged epidemics.
Seen in this light, the publication of the sequence changes resulting in mammal-to-mammal transmission (or of the sequence of a 1918 strain) can no longer be considered a reckless or naive act. Rather than being alarmed about the potential misuse of this research, we should be paying more attention to the detection and worldwide monitoring of new strains capable of holding their own against existing strains, and to strains exhibiting surface characteristics unfamiliar to the immune systems of much of the human population. And we should only really worry when such strains gain a foothold in parts of the world where poverty, malnutrition or unrest preclude an effective public health response.