Guarding the Henhouse

June 19, 2006

Years ago, when I started traveling to Centre County from New York City, I always got a kick out of the old "Entering Pennsylvania" sign that greeted us as we left Jersey behind.

"America Starts Here" the slogan proclaimed.

And—though it may have smacked of a certain anti-urban hubris—it also seemed true: Soon after sighting the sign, the
shopping malls and gas stations thinned out, the fields lengthened and got greener, the trees—and the deer in their shadows—grew thick along Route 80, and before long we'd find ourselves in a Wyeth painting, replete with that quintessentially American icon: a red barn surrounded by fertile farmland.

Quaint as they are, those red barns symbolize a mighty industry: Pennsylvania is a $45 billion dollar agricultural powerhouse
and the leading agricultural producer in the northeast. Contributing more than $750 million annually to the state's economy, Pennsylvania's poultry trade is one of the largest agricultural industries in the Commonwealth, second only to dairy.

So it may come as no surprise that Pennsylvania is also one of the most vigilant states in the nation when it comes to preventing and curtailing avian diseases. Working in tight collaboration with the
Pennsylvania Department of Agriculture and poultry producers (from small family farms to agribusiness chicken giants such as Tyson) Penn State plays an important
role in guarding this lucrative industry and protecting the safety of the state's 12.4 million residents.

The university began teaching poultry science in 1895 and its acclaimed department of poultry science (one of only seven nationwide) is on the frontlines of the war against bird flu in the Keystone state.

"We have a very sophisticated poultry industry in Pennsylvania," says Eva Wallner-Pendleton, field investigator and avian pathologist in the university's Animal Diagnostic Laboratory. "With an emergency disease grant from the U.S. Department of Agriculture, the university created a videotape on avian flu that's gotten a lot of circulation among our state's poultry companies and growers. It helps people stay on the alert."

In addition, says Wallner-Pendleton, "Penn State, the Pennsylvania Department of Agriculture, and other universities in the state regularly put on educational programs that always have a health component." The message, Wallner-Pendleton adds, is that the right professional practices can help prevent a devastating loss for Pennsylvania.

Pennsylvania has tasted such devastation before. In 1983-84, a highly infectious H5N2 strain of avian flu erupted among domestic poultry in the state. "It started as a low pathogenic strain and didn't cause much alarm at first," recalls Michael Hulet. "But it continued to circulate in the bird populations for about six months and then it mutated and became a highly pathogenic strain."

Adds Paul Patterson, the virus was eventually eradicated through quarantine and the extermination of over 17 million birds at a huge cost to the industry, up to $65 million lost." (Unlike the H5N1 strain circling the globe today, H5N2 didn't result in human illness or death.)

Patterson and Hulet are professors in the poultry science department, while Wallner-Pendleton, pathologist Patty Dunn and virologist Huaguang Lu are avian veterinarians at the Animal Diagnostic Laboratory. Together, they constitute Penn State's avian flu swat team, the first responders to a report of possible infection in the state. Depending on their areas of expertise, different team members perform necropsies on sick and dead birds to determine why they died; develop methods for the disposal of large numbers of poultry carcasses; decontaminate buildings; and train poultry producers on biosecurity protocols.

Our discussion of the lethal 1983-84 outbreak puts the team in a reflective mood. "It was an unfortunate event," says Wallner-Pendleton, as her partners shake their heads. "But it did change a lot of the ways the state views avian influenza. Since then, Pennsylvania has started regular monitoring programs. Before 1983, strains had the opportunity to circulate and mutate. Now, when we see any H5 or H7 strains, the goal is to wipe it out immediately."

The 1983 epidemic also put the spotlight on live bird markets as the source of many avian flu outbreaks. "There are bird markets all over the northeast, including five in Pennsylvania," explains Hulet. "But despite efforts to clean them up, the live bird markets in New York and New Jersey have had a low level of low-path bird flu infection almost continuously, particularly the H7N2 strain. The outbreak in '83 probably got started there."

hens in cage
Melissa Beattie-Moss

In the last two decades, new protocols have been developed to prevent lethal epidemics. "Flocks intended for the live bird
market are tested routinely," says Patterson. "They're either tested monthly as part of a monitored program or they're tested 10 days prior to going to market. They have to have an AI (avian influenza) clean blood test and certified paperwork before they can go into the market."

"This state is literally number one," Wallner-Pendleton chimes in. "Because we have 10 to 12 cases of low path bird flu here every year, we have one of the top surveillance programs in the country, with over a quarter million AI tests performed in Pennsylvania annually. A third of those quarter million tests are done by Penn State's Animal Diagnostic Laboratory."

What's more, she continues, "Mike, Paul, Patty, Huaguang and I are out in the field all the time visiting farms, we have three diagnostic laboratories in the state, and our poultry producers are generally very good about bringing birds to our attention if they see increased death losses in their flocks."

As media reports proliferate about a possible Asian bird flu pandemic, it's important to separate fact from fiction, cautions Wallner-Pendleton. How safe are we?

"Because our state has such an extensive plan for mild strains," answers Patterson, "it gives us a huge jump for picking up more dangerous strains if they come here. We've had a twenty year history of monitoring our birds, so I think it should give Pennsylvanians some reassurance."

"There's talk of it coming here by contact between migratory water fowl with domestic poultry, adds Hulet. "But our commercial birds are confined in buildings and we have tight biosecurity in the poultry industry to prevent that mixing from happening. This all adds up to protection for the birds and for the citizens of Pennsylvania."

Governor Rendell agrees. "The state has one of the most secure and prepared commercial poultry industries in the world," he commented at the state's
Pandemic Influenza Preparedness Planning Summit
held in Pittsburgh in March. Joined onstage by U.S. Health and Human Services Secretary Michael O. Leavitt and other state and federal homeland security, agriculture, and health experts, Rendell echoed the Penn State poultry experts' confidence and pride.

"Last month," said Rendell, "Pennsylvania became the first and only state in the nation to use mobile labs to test for biological and chemical threats that can occur naturally or by acts of terrorism. So, whether the threat is animal or human," he concluded, "Pennsylvania stands ready to act."

Eva Wallner-Pendleton, Ph.D., is senior research associate in the Animal Diagnostic Lab; Michael Hulet, Ph.D., is associate professor of poultry science; Paul Patterson, Ph.D., is associate professor of poultry science; Huaguang Lu, MPVM, is senior research associate in the department of veterinary and biomedical sciences;

Last Updated June 19, 2006