Bird flu virus still cause for concern: experts
By Maggie Fox
WASHINGTON (Reuters) - The H5N1 bird flu virus, which has now sickened more than 400 people globally, is infecting birds and people all across China and is still a cause for serious concern, flu experts said on Tuesday.
Recent cases are the expected winter seasonal surge seen for many types of viruses, they said, and there is no evidence that it is mutating into a more dangerous form.
"In the past three months, we have continued to see a great deal of activity," Dr. Keiji Fukuda of the World Health Organization told reporters.
Chinese officials confirmed a new case on Monday in a 23-year-old woman in Hunan province, who was being treated.
All the patients were around chickens, so there is little concern that people are passing the virus to one anther, the flu experts told a news briefing at a meeting in Washington of the Infectious Diseases Society of America.
"These cases and the widespread nature of them continue to point out how persistent this virus is and how widespread it is," Fukuda said. "We believe that the threat of pandemic influenza remains as high as ever."
Since 2003, the H5N1 avian influenza virus has infected 404 people in 15 countries and killed 254 of them. It has killed or forced the destruction of more than 300 million birds as it spread to 61 countries in Asia, the Middle East, Europe and Africa.
"This is a very unusual virus and the reason why it so unusual is that it is probably the most lethal influenza virus that has ever been discovered," Fukuda said. Continued...