Newswise — The simultaneous existence of bird flu and a particularly virulent form of human influenza circulating this season is the "perfect set-up for something weird and dangerous" to happen on the world health scene, according to a University at Buffalo expert on infectious disease and geographic medicine.
"The worry is that if the two flu viruses cohabitate in the same person they will exchange genetic information and produce an influenza strain totally new to humans that can be passed from person to person," says Richard V. Lee, M.D., professor of medicine at the UB School of Medicine and Biomedical Sciences.
"If that happens, we easily can have a pandemic flu on our hands," he says.
According to Lee and other experts, it probably will take four to six months to manufacture a vaccine to combat a human-to-human form of the bird flu.
In that time, the virus could spread around the world, Lee says.
"Humans have not had to deal with a major flu pandemic for 35 years (since the 1969 Hong Kong flu outbreak). "That could set the stage for something pretty dramatic to happen," he says.
Which is why the World Health Organization, World Animal Health Organization and Centers for Disease Control wisely are taking steps to get out ahead of the possible pandemic strain of bird flu, Lee says.
There also is the chance that the bird flu could jump back and forth between chickens, migratory fowl and other birds capable of spreading the virus across great distances, Lee warns. Or the bird flu could jump to pigs, undergo genetic changes that would produce infectivity among mammals, and then be transmitted to humans.
"When this new strain of bird flu comes into contact with a virus present in a pig, it could emerge from the pig with new genetic equipment to infect more pigs and humans, which would increase the risk of human-to-human infection," Lee says.
"What makes influenza viruses so special is their ability to infect and colonize in many different host species," he adds.
Lee, who studies the health status of geographically isolated human populations, is not surprised by the outbreak of bird flu, SARS, monkey pox and other viruses that seem to suddenly arise globally.
"There are places in the world that are a Pandora's box for certain kinds of infectious disease," he explains. "The way people live and interact with their environment sets the stage for letting these viruses out of their boxes."
Some of these places, according to Lee, include fish-farming villages in Southeast Asia -- where liver fluke infections, Japanese B encephalitis and Nipah virus threaten residents -- and agricultural communities in Africa that share boundaries with wildlife populations -- where the Ebola virus and African tick typhus are active.