The Threat of Pandemic Influenza: Are We Ready? Workshop Summary.

Scientifically we are better prepared; however the connected globe creates new vulnerabilities

In the early 20th century, science was sufficiently sophisticated to anticipate that influenza, which had twice reached pandemic proportions in the late 19th century, would recur, but was largely powerless to blunt the devastating impact of the 1918 (H1N1) pandemic. Since then, mankind has gained several advantages against the disease: experience of three better characterized pandemics (1918, 1957, and 1968); knowledge of influenza viruses; capacity to design and manufacture vaccines and antiviral drugs to forestall (if not prevent) infection; and molecular technology that may one day pinpoint the viral components that produce virulence, and thereby identify targets for more effective vaccines and drugs.

Yet the world is vulnerable to the next pandemic, perhaps even more than in 1918, when the pace and frequency of global travel was considerably less than today.

1918 came in three waves: 1918-1920

1918 seems to have been particularly violent. It began mildly, with a spring wave. In fact, it was so mild that some physicians wonder if this disease actually was influenza. Typically, several Italian doctors argued in separate journal articles that this “febrile disease now widely prevalent in Italy [is] not influenza” (Policlinico, 1918). British doctors echoed that conclusion; a Lancet article in July 1918 argued that the spring epidemic was not influenza because the symptoms, though similar to influenza, were “of very short duration and so far absent of relapses or complications” (Little et al., 1918).

Within a few weeks of that Lancet article appearing, a second pandemic wave swept around the world. It also initially caused investigators to doubt that the disease was influenza—but this time because it was so virulent. It was followed by a third wave in 1919, and significant disease also struck in 1920. (Victims of the first wave enjoyed significant resistance to the second and third waves, offering compelling evidence that all were caused by the same virus. It is worth noting that the 1889–1890 pandemic also came in waves, but the third wave seemed to be the most lethal.)