January 12, 2006

Bird Flu Evolving

From this morning's WaPo, by Daniel Williams and Alan Sipress:

ISTANBUL, Jan. 11 -- Preliminary tests show that the strain of bird flu virus that has stricken at least 15 people in Turkey has evolved in a way that could make it somewhat more hazardous to human beings, although it still lacks the capacity to be passed easily from person to person, international health officials said Wednesday.

The analysis, based on the sequencing of one of the virus's genes, suggests that at least some of the H5N1 bird flu virus here carries a change in one of its proteins, according to Michael L. Perdue of the World Health Organization. That protein is what lets the virus attach to cells and penetrate them.

"It's a little concerning because the virus is still trying new things in its evolution," said Perdue, who is overseeing the agency's response to the Turkish outbreak from WHO headquarters in Geneva....

Experts from the U.N. Food and Agriculture Organization warned that the virus could become permanently entrenched in Turkey, thereby increasing its risk to people and the chance it could evolve further. "The highly pathogenic avian influenza virus H5N1 could become endemic in Turkey," the organization said in a statement.

Two deaths have been attributed to bird flu in Turkey. The fatalities were the first outside China and Southeast Asia, areas where a total of 78 people have died in the past two years. More than 100 people have been hospitalized in Turkey with flu symptoms. The patients are under observation as they await test results to reveal whether they suffer from bird flu.

The virus has spread across 30 of Turkey's 81 provinces, from the far east to the Mediterranean coast, and has sparked a frantic effort to stem the disease by killing infected poultry. Even in cosmopolitan Istanbul, bird catchers for the Agriculture Ministry are rounding up fowl raised in the outskirts of the city, gassing them to death and burying them in mass graves....

"There is no transmission from human to human so far with a mutation of the virus," said Marc Danzon, WHO's regional director for Europe. "We are not there at the moment, but it is the responsibility for the WHO to look at this. . . . There is no reason to panic."...

Turkish health workers have killed more than 300,000 domestic birds in roundups across the country since late December. In one district of Istanbul, municipal sanitation officials went door to door in a rural hillside suburb asking residents if they raised chickens and ducks. They chased strays up and down the slippery, muddy hills and ravines, and when they caught one, they stuffed it into a plastic bag. Signs around the neighborhood read, "This District Has Chicken Plague."

Workers dressed in protective gear threw the bags into green containers that looked like large garbage cans. A sanitation worker attached a blue tube from a tank of carbon dioxide to the airtight container, opened the valve and killed the birds. "We prefer to say we are putting them to sleep," said Hikmet Karacay, an Agriculture Ministry official.

Residents, most of whom raised chickens as a sideline to collect the eggs, cooperated. "The real problem is the children," said Gilsen Kaya, who has two daughters. "They like the chickens. They are like pets. That's why it's better to do it at night, when they don't witness the whole thing."

It always amuses me when people say there's no evidence that species evolve. It happens all the time, within a brief time span, at the microbial level.