Bird Flu Spread Among Humans Would Be Deadly
Human Cases Mount, but Still No Giant Leap to Mankind
"This particular infection is clearly difficult to catch and seems to come about following very close contact with poultry. There is no evidence of human-to-human transmission among our cases," Farrar tells WebMD.
But there is some hopeful news. "In my hospital no more confirmed cases have been admitted to the hospital for two weeks," Hien says.
People get bird flu via close contact with infected birds or their feces. There is no evidence that people get the infection from eating fully cooked chicken or eggs. However, tigers in a zoo near Bangkok appear to have been infected with bird flu by eating raw chickens. CDC officials recommend fully cooking chicken and eggs for Americans living or traveling in areas where there's bird flu.
Bird Flu Deadly
In December 2003 and January 2004, Farrar and colleagues treated 10 patients with lab-confirmed H5N1 avian flu -- seven children and three young adults. They got sick two to four days after handling infected poultry.
Despite intensive treatment -- including, for eight patients, a flu drug that kills the H5N1 virus in the test tube -- nearly all the patients got worse. Eight of the patients died.
An earlier report of possible human-to-human transmission of the bird-flu virus has been discounted. Researchers now say everyone who has come down with the deadly virus came in contact with infected birds.
Why Experts Worry About Bird Flu
"The worry is that this strain reassorts [swaps genes] with another influenza virus and the 'new' strain has the capacity to cause a very severe infection and be transmitted between humans," Farrar says. "We have no evidence that this has happened in this outbreak, but it is a worry for the future. It is important to keep a perspective. Avian influenzas have been circulating for many, many years -- as have human influenzas. The reassortment that would be needed could happen now or not for another 1,000 years."
One worrisome development is that the bird flu has already jumped the species barrier to house cats. A Thai woman who had 14 cats lost them all to a mysterious illness. Three of the cats -- including one that had eaten a dead chicken -- tested positive for bird flu.