PDD Update

Public release date: 29-Jul-2008
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Contact: Kristen Bole
kbole@pubaff.ucsf.edu
415-476-2557
University of California - San Francisco
UCSF researchers identify virus behind mysterious parrot disease

Researchers at the University of California, San Francisco, have identified a virus behind the mysterious infectious disease that has been killing parrots and exotic birds for more than 30 years.

The team, led by UCSF professors Joseph DeRisi, PhD, and Don Ganem, MD, also has developed a diagnostic test for the virus linked to Proventricular Dilation Disease, or PDD, which will enable veterinarians worldwide to control the spread of the virus.

Results of the study will be published in Virology Journal and will appear online in August. The findings also will be presented in full at the August 11 annual meeting of the Association of Avian Veterinarians, in Savannah, GA.

The new virus, which the team named Avian Bornavirus (ABV), is a member of the bornavirus family, whose other members cause encephalitis in horses and livestock. Working with veterinarians on two continents, the group isolated this virus in 71 percent of the samples from infected birds, but none of the healthy individuals.

"This discovery has potentially solved a mystery that has been plaguing the avian veterinary community since the 1970s," said DeRisi, a molecular biologist whose laboratory aided in the 2003 discovery of the virus causing Severe Acute Respiratory Syndrome, or SARS, in humans. "These results clearly reveal the existence of an avian reservoir of remarkably diverse bornaviruses that are dramatically different from anything seen in other animals."

The discovery could have profound consequences on both domesticated parrots and in the conservation of endangered species, according to DeRisi and Ganem, both Howard Hughes Medical Investigators at UCSF. Those species include the Spix's Macaw, currently one of the most endangered birds in the world, whose number has dwindled to roughly 100 worldwide and whose continued existence is threatened by PDD.

The research was spearheaded by Amy Kistler, a postdoctoral fellow in the DeRisi and Ganem labs. Together with veterinarians Susan Clubb, in the United States, and Ady Gancz in Israel, Kistler analyzed affected birds using UCSF's patented ViroChip technology.

The ViroChip, which DeRisi and Ganem developed, is a high-throughput screening technology that uses a DNA microarray to test viral samples. The team was able to recover virus sequence from a total of 16 diseased birds from two different continents. The complete genome sequence of one isolate was captured using ultra deep sequencing.

The virus they identified is highly divergent from all previously identified members of the Bornaviridae family and represents the first full-length bornavirus genome ever cloned directly from avian tissue. Analysis of the Avian Bornavirus genome revealed at least five distinct varieties.

PDD is a fatal disease that causes nervous system disorders in both domesticated and wild birds in the psittacine, or parrot, family worldwide. The disease has been found in 50 different species of parrots, as well as five other orders of birds, and is widely considered to be the greatest threat to captive breeding of birds in this family, the researchers said.

The disorder often leads to the birds' inability to swallow and digest food, with resulting wasting; many birds also suffer from neurologic symptoms such as imbalance and lack of coordination. Regardless of the clinical course the disease takes, it is often fatal.

Scientists have theorized for decades that a viral pathogen was the source of the disease, but until now, no one had been able to identify the likely culprit.

"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."

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Co-authors on the paper include Amy L. Kistler, Peter Skewes-Cox, Kael Fisher, Katherine Sorber, Charles Y. Chiu and Alexander Greninger, from the Howard Hughes Medical Institute and Department of Biochemistry, Microbiology and Medicine at UCSF; Ady Gancz, from The Exotic Clinic, Herzlyia, Israel; Susan Clubb, Rainforest Clinic for Birds and Exotics, Loxahatchee, Fla.; Avishai Lublin, Sara Mechani and Yigal Farnoushi, of the Division of Avian and Fish Diseases, Kimron Veterinary Institute, bet Dagan, Israel; and Scott B. Karlene, of the Lahser Interspecies Research Foundation, Bloomfield Hills, MI.

The research was supported by funding to DeRisi and Ganem from the Howard Hughes Medical Institute and the Doris Duke Charitable Foundation. Funding for US specimen collection and veterinary care was provided by the Lahser Interspecies Research Foundation

The DeRisi Laboratory is part of the California Institute for Quantitative Biosciences, known as QB3, a cooperative effort among private industry and more than 180 scientists at UCSF, UC Berkeley and UC Santa Cruz. The collaboration harnesses the quantitative sciences to integrate and enhance scientific understanding of biological systems at all levels, enabling scientists to tackle problems that have been previously unapproachable.

UCSF is a leading university dedicated to promoting health worldwide through advanced biomedical research, graduate-level education in the life sciences and health professions, and excellence in patient care. For further information, please visit www.ucsf.edu.

Weekly Piano Lesson

aarrrgggghhhhh . . . chords!

The Law

Spent over half an hour on hold yesterday trying to speak to an IRS agent, to find out why I haven't received my incentive check. I'm so not looking forward to calling again.

Got a summons today for jury duty. I don't mind jury duty that much; I really do think it's my responsibility as a citizen. Old-fashioned, I know.

And, of course, spent nearly half an hour on the phone with GoDaddy this morning. Perhaps I should just move there.

The Evil Committee began its down-hill slide yesterday; some things got done incorrectly and there was confusion so we left early. I haven't figured out a way to smuggle whiskey into the meeting room, though. Which is probably for the best.

Sugar Franklin was perkier than usual yesterday, running back and forth in her cage until I brought her out where she proceeded to run back and forth on the coffee table and on me.

I love the way parrots (and I guess other pets) just assume possession of a human's body. Charli will move from the back of the couch by hopping onto my shoulder (without asking, of course) and then scoot herself to my chest so that she's in perfect position to be scritched and then to take a nap. Like I was put on earth to meet her needs and wishes, and that I wouldn't dare move lest I inconvenience her. My parrots have claimed my shoulders, my back, my knees, my chest, and my lap, and sometimes my feet -- though my feet are loudly proclaimed by Sugar Franklin to be Evil and in dire need of hissing at.

What I wouldn't give to know what they think.

No Good Deed

I went out for an early supper and when I got home two women were sitting on the porch next door; one looked like a teen-ager, the other in her late twenties. From what I could tell the guy had not yet come home from the hospital nor had the woman with the two babies returned. There were no cars in the drive or in front of the house.

I asked how things were, and the women said their dad was okay. Hmmm, he didn't look old enough to be these women's father, but I'm a terrible judge of age.

The older one asked to use my phone so I said, "No long distance, right" She shook her head and made her call. She talked for about five minutes then gave me back the phone. I checked the number and sure enough -- it was out of our area code. I went across the yard and said she'd have to pay for the call, that I don't have free long distance. She looked astonished and said she'd only called her sister. I repeated that it was long distance. Then she said she only talked for a minute. Like that took care of everything.

sigh . . .

I said I'd bring the bill over when it arrived and would expect to be paid then.

Yeah, right, like I'll ever get a dime out of her.

O, my piano teacher, is also a rental agent for this neighborhood. She happened to mention a few months ago that she'd signed up a nice young quiet woman with a baby to rent the house next to me. I nodded and said they'd all been moving in the weekend before.

"They?"

"Yeah, she's young and he's maybe in this 30s or 40s and some other guy."

"No," she said. "This was a young blond woman with a baby."

"Nope," I responded. "These people are black and I haven't seen a baby." I don't care who lives next door to me as long as they're quiet, don't throw trash in my yard, and aren't making meth or holding sex slavery auctions. In the years I've lived here I can't count the number of folks who've moved in and out of the rental houses on either side of me.

I could tell O was confused by who I said was living there, but I haven't mentioned it to her since, and I don't know what she did about it. Or if she did anything about it. There's also been a woman who faintly seems Asian coming and going who's always got her hair wrapped in a towel as if she'd just gotten out of the shower. And lots of other friends who come and go.

Well, I won't lend my phone to any of them again.

It's been a nice day today. Beautiful weather, though maybe 10 degrees too hot for me. I had the cockatiels out for a couple of hours, watching their busy goings and comings. Then I had Charli out for a couple of hours and scritched her head for most of that time.

Tomorrow starts the work week, then I have to get serious about getting myself ready to go to Vermont week after next. I've already made arrangements for L to bird sit for me, so I've got to get the keys to her soon.

I wish I could stay home from work like my birds and have someone scritch my head.

Update: Someone rang my doorbell twice at 11:30 pm, but I was too tired to get up. And this morning there's yet another out-of-state car in their driveway.

Hey -- I'm the nosey neighbor; it's my job to look as I drive off.

Rental Property

Instead of taking a nap yesterday afternoon I decided to get my hair cut. I informed the birds of my intention and opened the front door.

To find an EMS truck, complete with flashing lights, blocking my driveway. I walked out to the porch just as the paramedics brought out a stretcher from next door, carrying the young man who lives there. Well, I assume he lives there -- he's there a lot but then so are a lot of other people. It's a rental house so I never know.

Anyway, the paramedics loaded him into the truck and climbed in after him. And then nothing. I, based on my vast knowledge of EMS and ER activities based on my extensive reading of medical blogs, knew they were probably getting vitals and starting an IV.

I noticed the storm door had been propped open, so I went over and closed it then went back to my porch. A few minutes later the wife/girlfriend/young woman came hurrying out, carrying two babies in carriers. I didn't realize there was anyone else inside; otherwise I wouldn't have bothered the storm door. She got them settled in just as one of their friends drove up. She called to the friend and they talked for awhile.

And still the EMS truck didn't move. I wasn't in a hurry so it didn't matter to me how long they parked there.

Finally the truck pulled out. I waited until it was well on its way off my street, then started my car and backed out. The friend was getting back into his car, so I rolled down the window and asked if everything was okay. (duh) He said yes, his friend couldn't move his hip and the paramedics wouldn't let him enter the truck to see his friend.

So I guess it's official now -- I'm the nosey neighbor.