NEW YORK (CNN/Money) - Coal miners used to bring canaries underground as an early warning system, because the song birds dropped dead from poison gas before it sickened humans.

Household pets now serve as proverbial coal mine canaries in detecting outbreaks of bird flu pandemic, bioterrorist attacks, and other contagious catastrophes, thanks to a nationwide system developed by the Centers for Disease Control, Purdue University and Banfield, The Pet Hospital.

"We hope that in using pets as sentinels we'll be able to pick something up that's important to human health," said Dr. Hugh Lewis, senior vice president for Banfield, a chain of more than 500 veterinary hospitals that is partly owned by retailer PETsMART (up $0.27 to $22.42, Research).

The bird flu virus, also known as H5N1, can be transmitted from birds to humans and has killed more than 60 people in Asia. Scientists recently discovered that the 1918 influenza pandemic that killed more than 50 million people originated in birds, and health officials fear that the constantly-mutating H5N1 virus could someday transmit from human to human.

To answer these concerns, the CDC has provided funding to Purdue University to establish a "syndromic surveillance" system to detect viral hot spots in pet populations. The researchers use Banfield's PetWare database of eight to nine million pets to detect viral outbreaks and other health problems. The database tracks pets from 44 states.

Dr. Larry Glickman, Purdue professor of epidemiology and director of the syndromic surveillance system, said that PetWare is the only database of its kind in the country. There is no nationwide or regional database for human health care because hospitals are not coordinated, said Glickman. So household pets, not humans, could provide the first signs of a lethal outbreak, especially since 40 percent of all Americans households have a cat or dog.

The first reaction to an outbreak would be to control it, and then the virus would be studied once it's contained, said Dr. Glickman.

"If the canary falls down, you don't wait for a diagnosis," said Dr. Glickman. "You get the hell out of the mine and examine the canary later."

PetWare was developed in the late 1980s at Banfield's original hospital in Portland, Ore. and the company is currently adding more than one million pets per year to the database, said Dr. Lewis, who is also the president of Data Savant, a software consulting company. PetWare was originally created as a veterinary tool, but this year it attracted the attention of the CDC and Purdue.

Cats, not canaries, will serve as sentinels for bird flu, said Dr. Lewis. There are 70 million cats in America, which makes them more common than songbirds and a more reliable source of information. An H5N1 outbreak at a Thai zoo laid waste to its tiger population, which had been fed infected chickens, revealing the feline vulnerabilities to the virus. So far, dogs have not proven susceptible to bird flu.

The syndromic surveillance system was started about three months ago. Dr. Glickman is particularly interested in anthrax and tularemia, diseases that are transmitted from animals to humans. Dr. Glickman said he was contacted by the Department of Homeland Security around the time of the Sept. 24 anti-war protests in Washington, D.C. after the CDC detected tularemia in the air above the capital through its Biosense air filter systems.

Dr. Glickman said he accessed PetWare and found no further evidence of tularemia, a sometimes fatal virus known as rabbit fever, in the Washington, D.C. area. However, this situation revealed a glitch in the system, because Dr. Glickman was unable to access the database in a timely manner. He said the system has since been improved, with Purdue now receiving daily updates on the PetWare database.

Dr. Glickman said he would like to improve the system further, by having 24-hour access to the PetWare database.

"With a small infusion of resources we will have this system in place to work with anyone from Homeland Security," said Dr. Glickman.

To read more about Banfield and the $12 billion veterinary industry, click here.