Tuesday, October 11, 2005

A killer back from the dead

Only a week or so ago I was lamenting that few Americans were aware of the threat of avian flu. Now suddenly, the story is everywhere. No need to rehash here the potential catastrophe that has in recent days been splashed all over the media.

But here is another story, and an important one: Biologists have recreated the virus responsible for the 1918 flu pandemic that killed as many as 50 million people worldwide. Fragments of viral RNA were retrieved from a flu victim buried in Alaskan permafrost in 1918. The RNA was converted into DNA and sequenced. Overlapping sequences were pieced together to get the entire genome, and the viral DNA was synthesized in the lab. The synthesized DNA was injected into human kidney cells, which produced tens of viruses. These were isolated and used to infect mice. The mice all died within days of a virus that was indeed many times more virulent than the pathogens responsible for the pandemics of 1957 and 1968.

A century old flu virus has been recreated. Good or bad? Some say good. The team that synthesized the virus got permission from the Centers for Disease Control and the National Institute of Allergy and infectious Diseases, the relevant national overseers. Apparently, they consider the benefits outweigh the risks. As it turns out, the 1918 virus was derived wholly from a bird virus, and thus may help understand the current threat and perhaps hasten the development of effective vaccines. Others say bad. What has in fact been recreated is a virulent killer that might escape the laboratory by accident or malfeasance. The DNA sequence of the 1918 virus has been published, available to any terrorist organization that might muster the technical requirements to recreate the virus. Not quite the Jurassic Park scenario, but not far from it.