Posted: July 31, 2008, 3 p.m. EDT
PDD was once known as "Macaw Wasting Disease."
Courtesy Terry Trammell, Georgia
Researchers at the University of California, San Francisco, say they have identified the virus linked to Proventricular Dilatation Disease (PDD), a fatal disease that causes nervous system disorders in both domesticated and wild birds in the psittacine, or parrot, family. PDD has been found in 50 different parrot species, as well as five other orders of birds, and is considered to be the greatest threat to captive breeding of birds in this family, according to UCSF.
The researchers also developed a diagnostic test for the virus. The virus, which has been named Avian Bornavirus (ABV), is a member of the bornavirus family, whose other members cause encephalitis in horses and livestock.
“This discovery has potentially solved a mystery that has been plaguing the avian veterinary community since the 1970s,” said Joseph DeRisi, Ph.D., who led the team with Don Ganem, MD, both professors and Howard Hughes Medical Investigators at UCSF. “These results clearly reveal the existence of an avian reservoir of remarkably diverse bornaviruses that are dramatically different from anything seen in other animals.”
Drs. DeRisi and Ganem said that the discovery of the ABV virus could have profound consequences on both domesticated parrot species and in the conservation of endangered species.
It had been theorized that a viral pathogen was the source of the disease, but until now, no one had been able to identify it.
“This provides a very compelling lead in the long-standing search for a viral cause of PDD,” Ganem said. “With the development of molecular clones and diagnostic tests for ABV, we can now begin to explore both the epidemiology of the virus and how it is linked to the disease state.”
The study, which will be published in Virology Journal, is also co-authored by Amy Kistler, Ph.D., from the Howard Hughes Medical Institute and the Department of Biochemistry, Microbiology and Medicine at UCSF; Susan Clubb, DVM, from the Rainforest Clinic for Birds and Exotics in Loxahatchee, Fla.; and Ady Gancz, from The Exotic Clinic, Herzlyia, Israel; among others.