Downloadable map helps track avian flu

University Of Colorado, Ohio State University By Bill Scanlon, Rocky Mountain News

Published May 3, 2007 at midnight

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Avian flu has less of a chance to sneak up on a continent, a country or a city, thanks to a new "supermap" created by researchers from Colorado and elsewhere.

The downloadable map traces the spread of H5N1 avian flu from the mid-1990s in Guangdong, China, to southeast Asia, Africa, the Philippines and Europe - a unique visual record over space and time.

Different colors show the mutations and the animals infected, helping scientists predict which mutations might make the virus an efficient transmitter to human beings.

Avian flu so far has killed at least 172 people, most of whom had direct contact with infected birds - usually in the form of backyard poultry, or poorly cooked ducks.

The death rate of infected people officially is at about 59 percent. But that could be way too high, considering that many people who got infected might not have gotten sick, and many others who did get sick may not have sought medical care.

That would put the denominator - the total number of humans infected - in the thousands, and dramatically lower the death-to-infection ratio.

Avian flu H5N1 has not reached North America, although experts predict it's only a matter of time before migrating wild birds bring it here. It likely will be passed on to domesticated poultry.

The big question is whether it can mutate to the point where it can infect humans who don't directly touch infected birds.

The unique map shows the spread of avian flu in waterfowl, ducks and hens, shorebirds, raptors, songbirds, hoofed mammals and carnivores, said CU- Boulder ecology and evolutionary biology assistant professor Robert Guralnick. He's one of the co-authors of a study that appears in the current issue of Systematic Biology.

The team, which also includes scientists from Ohio State University and the American Museum of Natural History, used Google Earth technology to allow users to fly virtually around the planet and analyze changes in the genetic blueprints of the virus over time and space.

"This is a completely new method of integrating and sharing knowledge about disease spread," said CU-Boulder graduate student Andrew Hill, another co-author. "It gives people a quick and easy way to make sense of the changes."

By tracing two proteins, the map makers found that those two markers haven't mutated as they have spread across half the world. That's good news, because if they stay in their current form, mammals can't be easily infected.

But they're also watching a virus genotype, Lysine-627, that appears to be very deadly in mice, and could prove harmful to humans and other mammal hosts.

Lysine-627 helps determine how infective avian flu can be in mammals, Guralnick said. "Whether that is a threat or not is tough to say."

Anyone with the more recent incarnations of Google software can access the video of the avian flu map, but would need extra knowledge to understand the details, said Hill.

Tracing spread of avian flu

This video "supermap," using Google Earth technology, tracks the spread of avian flu. To see the map, go to: www.researchnews.osu.edu/archive/flumap.mov

University Of Colorado, Ohio State University

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