WOOSTER, Ohio – It could be called the turkey cold, and it attacks cold turkeys fast.
Young gobblers infected with avian pneumovirus sneeze, cough and soon produce a frothy nasal discharge accompanied by foamy conjunctivitis. Within days, many of them die.
Although avian pneumovirus hasn’t been found in Ohio, scientists with Ohio State University’s Ohio Agricultural Research and Development Center are studying the disease to be prepared for its possible arrival.
“Respiratory diseases are the most dangerous in turkeys,” said Mo Saif, head of center’s Food Animal Health Research Program. “We needed to get acquainted with the virus because we don’t know if it will get into Ohio. It could be a serious problem.”
Newer virus. Common in Europe and other parts of the world, avian pneumovirus was first diagnosed in the United States six years ago in a Colorado turkey flock.
The disease was eradicated in Colorado but has since victimized flocks in Minnesota and North and South Dakota, which are among the country’s top turkey producers.
Thus far, there is no evidence of the virus anywhere else in the country.
In Minnesota, where APV has been endemic since 1997, the turkey industry has experienced losses of approximately $15 million per year.
No U.S. vaccines. “The Europeans have used vaccines to fight this virus,” Saif said. “However, we don’t have any vaccines available in the United States right now because the disease hasn’t become a major national problem.”
As part of the research, Ohio State scientists have developed tests to effectively diagnose the disease in case it reaches the Buckeye State, which ranks 12th in the nation in turkey production, according to the USDA.
In 2001, Ohio produced 4.8 million turkeys with a value of $63.5 million.
First reports attributing APV to a respiratory disease -known in turkeys as turkey rhinotracheitis (TRT) and in chickens as swollen head syndrome – came from South Africa in the late 1970s. From there, TRT spread to Israel and Europe, and in 1986 the causal agent was identified in the United Kingdom as an avian pneumovirus.
Different strain. However, the virus identified in the United States proved to be serologically different from other avian pneumoviruses isolated worldwide from turkeys and chickens.
Rapid spread. Avian pneumovirus causes upper respiratory infections with sudden onset and rapid spread through flocks. All ages of turkeys are susceptible, but the disease is more severe in young birds.
Victims experience conjunctivitis, rhinitis, sinusitis and tracheitis. In some cases, every bird in a flock will get infected and up to 90 percent may die. In addition, a decline in egg production has been observed.
Recovery usually takes place within 10-12 days, and egg production returns to normal within two to four weeks.
No chicken cases yet. Although avian pneumovirus can also affect chickens, no cases of swollen head syndrome or similar diseases have been reported in the United States or Canada.
The virus is also known to infect guinea fowl, ostriches, pheasants and other game birds.
“This disease is very similar to other respiratory diseases in turkeys, and it’s hard to differentiate it,” Saif pointed out. “That’s why we wanted to learn as much as possible about it.”
Transmission. Nasal discharge, contaminated water, equipment, feed trucks and movement of affected poults can contribute to the transmission of the virus.
Wild birds and reservoirs are also suspected in the spread of the disease.
Because the virus is shown to infect the epithelium of the oviduct of laying turkeys and because avian pneumovirus has been detected in young poults, egg transmission is also considered a possibility.
More questions about the transmissibility of avian pneumovirus remain.
In Minnesota, most outbreaks occur between March and May and between October and November, suggesting that environmental factors may contribute to the disease. One of the suspected sources of the outbreaks is wild birds, which have been found to carry the virus.