By Jonathan Berlin

Special to The Sentinel

Despite two incidents of avian flu among birds in and around Maryland since last September, the state is at low risk for the type that presents a danger to humans, said government authorities.

It is possible for low-pathogenic types of avian flu, which are common to waterfowl, to mutate into a form that is dangerous to humans, said Karen Eggert, a spokeswoman for the USDA's Animal and Plant Health Inspection Service. No incidents of high-pathogenic avian flu have occurred in the United States, she added.

State veterinarian Guy Hohenhaus said the likelihood of mutation is "as close to nil as you can get" because of the strength of Maryland's early detection program.

National standards require that the poultry industry test 98 percent of flocks for avian flu before they go to slaughter, said Eggert. In Maryland, the standard is even tougher – 100 percent within 10 days of slaughter, said Hohenhaus. The difference is insignificant in scientific terms but important to consumer confidence, added Hohenhaus.

The state also has a registry of poultry growers. Based on legislation the General Assembly passed in 2005, the registry consists of small and large holders of four types of poultry: meat chickens, egg chickens, meat turkeys and exotic or backyard birds, said Hohenhaus.

While the state Department of Agriculture already had easy access to the industry databases of large-scale chicken growers such as Purdue Farms and Tyson Foods, the registry facilitated the monitoring of "the folks who have a bunch of show chickens and 4-H club chickens," added Hohenhaus.

Last year during Labor Day weekend, the registry proved valuable when an Ohio State research project reported low-pathogenic avian flu among wild mallard ducks in Queen Anne's County. The state referred to the registry to identify all poultry operations within a 10-mile radius, then checked them and documented that the virus had not spread, said Hohenhaus.

The Department of Agriculture's detection program extends beyond state lines to head off potential outbreaks. At the end of March, Maryland officials assisted West Virginia in testing turkeys for low-pathogenic avian flu on a farm that produces for the Virginia Poultry Growers Cooperative.

The testing is as much for the birds as for humans. The risk of a low-pathogenic avian flu mutating to a form that is highly pathogenic for birds is "moderately low" but still greater than for humans, said Hohenhaus.

If testing shows evidence of avian flu, the procedure is drastic. For any flock that gives a positive test, "those chickens would be destroyed in the house, on the farm," said Connie Parvis, a spokesperson for Delmarva Poultry Inc. The flock would be composted in the house at temperatures high enough to destroy the virus, she added.

In West Virginia, authorities euthanized all 25,000 chickens at the farm where they found avian flu. Relative to the scale of the poultry industry, that property was a small operation, said Hohenhaus.

Aside from potential health effects for birds and humans, the economic effects of a positive test are enormous. Immediately after the discovery of low-pathogenic avian flu in Queen Anne's County, Russia imposed an embargo on all poultry from the Delmarva peninsula, said Hohenhaus.

The embargo had a negative impact on major poultry companies, as well as the several thousand families that raise chickens and the trucking industry that supplies propane and feed, he said. The Delmarva poultry industry exports "a significant chunk" of its chickens to Russia, he added.

When the Department of Agriculture documented that the avian flu had not spread, Russia lifted the embargo, Hohenhaus said.

Prince George's County posts information about avian flu on its website, but it does not participate in prevention efforts.

"We don't have the farms located in Prince George's County," said Gwen Clerkley, deputy director of the county's health department. The bulk of the work is taking place in the eastern Maryland because of its concentration of poultry operations, she added.