Bird Flu Spread Among Humans Would Be Deadly
Human Cases Mount, but Still No Giant Leap to Mankind
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.
Daniel S. Shapiro, MD, co-author of an editorial accompanying Hien's study, says the ability of the H5N1 virus to jump from birds to cats is ominous. He is director of the clinical microbiology labs at Boston Medical Center and an associate professor at Boston University School of Medicine.
Shapiro tells WebMD that what we know about bird flu so far increases our wariness that it could enter an animal population such as pigs, and offers the potential to eventually infect humans.
However, Shapiro says he thinks Americans should worry more about drunken drivers than the odds-off threat of a human version of bird flu. But he does express concern over what might happen if the bird flu spread through U.S. livestock. The H5N1 bird flu hasn't spread to the U.S. But this week, the USDA announced that there has been an outbreak of a different version of bird flu among poultry near San Antonio.
A few weeks ago, the Southeastern Center for Emerging Biologic Threats and Emory University held a meeting on pandemic influenza. The co-chair of that meeting was Jeffrey Koplan, MD, MPH, former CDC director and longtime CDC disease detective, now vice president for academic health affairs at Emory University in Atlanta.
At that meeting, flu experts agreed that a human version of the H5N1 bird flu would be a global disaster.