Posted: June 27, 2008, 5 a.m. EDT
Cockatiels and other birds can transfer psittacosis to humans if preventative measures are not taken.
Most pet bird owners never have to worry about the infectious disease psittacosis putting their lives at risk. According to the Centers for Disease Control and Prevention, the United States had fewer than 50 cases of psittacosis in humans reported each year between 1996 and 2005. Two members of a Corpus Christi, Tex., family were not only among this minority, but they faced the disease’s most severe effect.
Joe de la Garza Sr., 63, died in 2006 after allegedly contracting psittacosis from a cockatiel his daughter Amanda purchased at the city's PetSmart store, according to a June 18 article in Corpus Christi's Caller-Times newspaper. In the article, Amanda said she also came down with the disease, which left her hospitalized for about six weeks. Joe's family is now suing PetSmart in a wrongful death lawsuit, claiming Joe Sr. died after catching the illness from the bird.
The de la Garza family's case may be rare, but psittacosis is a concern for many pet bird owners. Also called parrot fever, psittacosis is caused by the bacterium Chlamydophila psittaci and is a zoonosis, meaning it can be transmitted from animals to humans.
“Why some infected birds cause infection in people and others do not is not known,” said David Phalen, DVM, Ph.D., DABVP (Avian), “but it may have something to do with the strain of the bacterium, the amount of exposure to the bird’s droppings and the person’s own immune system.”
Margaret A. Wissman, DVM, DABVP, Avian Practice, said among the newly purchased birds she sees in her practice, about 5 percent have an out-of-the-ordinary blood test or otherwise make her suspicious that the bird could have psittacosis. Phalen sees fewer than three or four cases per year, and he said the number has been decreasing.
Smaller birds, such as cockatiels, budgies (parakeets) and lovebirds, have a fair amount of psittacosis, Wissman said. As in the de la Garza family’s case, cockatiels are often carriers. Phalen said these birds may show no signs of infection at all, while larger species of parrots usually get very sick with psittacosis.
A bird with psittacosis can have variable signs depending on the organ system(s) it affects, including respiratory problems, loss of appetite and ruffled appearance. Wissman said the effects of the disease depend on the immune system of the bird versus the strain of the organism.
"It's a disease of like 100 different presentations," Wissman said. "You can have a bird very ill sitting on the bottom of the cage ... and you can have a bird that presents a little bit of conjunctivitis."
In humans, Wissman says, psittacosis presents itself as the flu, a bad respiratory infection, pneumonia or even mononucleosis. Wissman has experienced some of these symptoms herself, having been previously afflicted with the disease.
"It was like a cold that just wouldn't go away," Wissman said. "I had an irritating cough in my chest, and it kind of hurt to expand my lungs. After it didn't go away for three or four weeks, I went to my doctor."
Diagnosing and Treating Psittacosis
Diagnosing psittacosis can be difficult because no one test will definitively prove the bird has the disease, Wissman says. She knows of six tests veterinarians use, though the elementary body agglutination- or EBA- test is not currently available in the United States.
Tips to Prevent Contracting Psittacosis
Use these tips to prevent you and your bird from contracting psittacosis. More>>
Humans who suspect they have psittacosis might have trouble getting a diagnosis as well. Wissman says many physicians may diagnose it as the flu or a rhinovirus because its symptoms can be similar. She recommends seeing an epidemiologist for specific psittacosis testing.
Treatment for both birds and humans with the disease is with the class of drugs called tetracyclines. Phalen says veterinarians usually treat birds with doxycycline for 45 days in oral or injectable form. Human treatment lasts 10 days and involves taking oral antibiotic capsules.
Though psittacosis is not a common disease in people, it can cause fatality. Pet bird owners can follow guidelines to prevent contracting psittacosis - or other diseases - from their birds.
Phillip Feret, first vice president of the National Cockatiel Society and a cockatiel breeder since 1990, said observation is his "best defense" against catching a disease from a member of his flock. Feret's strategy is "to look for a bird that's not acting like the other birds."
"By the time most people realize that their bird is acting differently, the bird is going into near-death experience," Feret said. "If you just stand and look at a bird and look at what it's doing, it can tell you a multitude."
Veterinary examination can also be key. Wissman said that while avian veterinarians can't always diagnose psittacosis in a live bird, pet bird owners should take their pets in for a health exam and recommended tests. If a bird is showing signs of the disease, Phalen says, this veterinary visit should be immediate.
Quarantining new birds can help keep humans and other pets disease-free as well.
"Once you have a nice, stable flock," Wissman said, "don't bring in new or sick birds without talking to your vet and establishing a quarantine or isolation program for the new birds.”
Although humans can die from psittacosis, Feret says, owners shouldn't panic and get rid of their birds if the animals contract it.
"This is not the dreaded disease that we've been told about because the No. 1 thing about psittacosis is that it's treatable in people and birds," Feret said. "Almost every other disease in birds … there's no treatment."