January 4, 2012. The year was 2004 and I was sitting in an audience listening to Robert Webster, a world-renowned flu expert and virologist at St Jude Children’s Research Hospital in Memphis, Tennessee. He was talking about a relatively new strain of avian flu virus that was killing wild birds, poultry, and mammals, including some humans, at an astonishing rate of speed, in small animals, sometimes in a matter of hours.
Believed to have originated in southern China’s Guangdong Province, in 1997, the virus suddenly began infecting humans in Hong Kong, and later turning up in Southeast Asia, parts of Europe and Africa. The source was eventually traced back to the live poultry markets that provided direct contact between the infected chickens and humans. Dr. Webster stated that he had never seen a virus spread across multiple species barriers with such efficiency, and to such a degree of lethality. The flu virus was identified as A(H5N1), an avian virus that was capable of also infecting humans. Since then, A(H5N1) is now recognized as being endemic in poultry and wild birds in certain parts of the world today.
And for that reason, flu experts like Robert Webster worry that A(H5N1) virus could mutate and become the next great flu pandemic killing massive numbers of people. The last big one to occur, in fact the biggest epidemic in human history, the 1918 “Spanish Flu”, resulted in upwards of 100 million deaths worldwide (some credible sources peg this number closer to between 20-40 million), killing 2% of those who became infected with the virus.
As World War 1 was ending, in less than a year’s time, the global flu pandemic killed more people than those who died from the war itself. Although the A(H5N1) virus has infected only a comparatively small number of people (in the hundreds since 1997), the virus is significantly more lethal than the 1918 flu virus subtype H1N1, killing 50% of those who become infected, though fortunately not known to be transmissible from person to person.
In order for a pandemic outbreak to occur, a virus must mutate in just the right fashion to allow for human to human transmission to easily occur, be highly pathogenic, and target a largely virgin population, those not possessing protective immunity from prior exposure. The H1N1 variant met all three conditions in 1918, though scientists still are not sure exactly why.
The normal flu virus in many ways represents an ideal candidate for widespread disease transmission because the virus mutates rapidly, at least partially evading the bodies native immune response, and can be readily spread from person to person through air and casual human contact. Characteristically, although tens of thousands may die each year from the common flu strains, because we have built up a fair degree of immunity from previous exposure, it poses the greatest danger to the elderly and those with weakened immune systems.
Not true with the A(H5N1) virus and the 1918 H1N1, they mainly target those whose immune systems are the strongest; it’s the infected person’s heightened immune response that causes much of the internal damage in the body. Although this virus has shown signs of attacking organs throughout the body, including the brain in other species, in humans like other influenza viruses, it targets mostly the lungs.
Recently, the Hong Kong government ordered a large population of chickens from their live poultry markets destroyed because the virus turned up in dead chickens that were tested.
A rift may have developed between infection disease researchers, and The National Science Advisory Board for Biosecurity, created in 2004 to ensure that published information does not contain secrets that could help rogue states or terrorist groups develop their own biological weapons. This has become a more urgent concern when two separate teams of researchers successfully modified the H5N1 strain into a highly infectious, human transmissible strain, and in their (as yet) unpublished report submitted for review, detail how they accomplished this feat.
From the researchers perspective, there is strong resistance to even a hint of censorship. The goal of science is to solve problems, and the ability to freely share timely information amongst colleagues is its lifeblood. By understanding how the virus can become more virulent, the hope is that this information will lead to development of an effective vaccine, better treatments, and to sound an early warning when naturally occurring mutations evolve toward a more dangerous state.
Understandably, at least on the surface, the advisory panel wants to limit the type of information that gets published, for fear that information could provide a recipe for terrorists to develop their own weaponized avian flu virus. For an interesting interview with the lead author of this report, read this New York Times article: Security in Flu Study Was Paramount, Scientist Says. In addition, this NYT article Debate Persists on Deadly Flu Made Airborne talks about the A(H5N1) virus experiments at the Erasmus Medical Center in Rotterdam, and with Ron Fouchier, their lead virologist whose team successfully altered the already lethal virus into the capability of a deadly pandemic strain.
Infectious disease experts expect another pandemic disease will kill millions of people. If not from an A(H5N1) avian flu virus— from other viruses that exist in nature. As they mutate or suddenly come into contact with human populations, they pose a constantly evolving threat.
Lest we not forget, Mother Nature possesses her own weapons of mass destruction and she knows how to deliver them.
Additional resources:
- A Public Policy Expert Looks at the Bird Flu Threat
- The Coming Plague by Laurie Garrett