Avian Bird Flu Perspective

Avian Bird Flu Perspective

An article in this week's issue of the New England Journal of Medicine reviews significant achievements in molecular biology that hold great importance as the world faces the potential for an avian bird flu pandemic.

Robert Belshe, M.D., from Saint Louis University School of Medicine, says these achievements may enable us to track viruses years before they develop the capacity to replicate with high efficiency in humans.

One of the achievements noted is the recent genetic sequencing and recreation of the virus from the 1918 flu pandemic. The 1918 pandemic killed 675,000 Americans at a time when there were only 100 million people in the United States. Worldwide, the 1918 flu killed between 50 million and 100 million people. Dr. Belshe says this new sequencing and recreation of the 1918 epidemic will be extremely helpful in determining the events that may lead to the adaptation of avian viruses to humans before the occurrence of pandemic influenza.

Dr. Belshe says scientists should conduct worldwide surveillance to monitor this adaptation process. He says: "It gives us some reassurance that by continuing to monitor the current virus in birds, we can get a sense as to when it'll be an efficient virus. We may have some time to develop new vaccines and better therapies."

In his review, Dr. Belshe says the prospect of a new worldwide pandemic during the 21st century could involve either of two possibilities: A direct spread of an entirely avian virus from birds to humans, which is what happened during the 1918 Spanish flu, (the deadliest of last century's three pandemics) or a re-assortment virus that mixes bird flu with human influenza strains that are already circulating -- in effect creating a new strain.

Dr. Belshe says, "We don't know what will happen or when it will happen, but we know it will happen."

SOURCE: The New England Journal of Medicine, 2005;353:21