Adenovirus Related Articles
Atadenovirus-- This Disease Can Be Deadly to Your Bearded Dragon
Also known as wasting disease and stargazing disease, this bearded dragon disease can be fatal to your beardie.
By Kevin Wright, DVM, DABVP (RA)
January 27, 2012
Atadenovirus is a contagious disease that can cause serious illness in bearded dragons. Older literature refers to it as adenovirus. It may also be known as "wasting disease" and "stargazing" disease, among other terms. Unfortunately, this virus is very common in bearded dragon (Pogona vitticeps)collections and can be fatal.
What to Look For
ADV-positive dragons are more likely to be seriously ill from intestinal parasites, such as coccidian, flagellated protozoa, amoebas and nematodes. Others go on to develop bacterial infections of their intestine or liver. Those that make it past the 90-day mark often have trouble fighting other infections throughout their adult lives.
Some ADV-positive dragons end up with damaged livers and intestines, are always on the thin side and sleep a lot more than a virus-free dragon. In some ADV-positive dragons, the virus spreads to the brain and spinal column, and causes a twitching of the toes and tail tip, arching of the head and tail (sometimes known as stargazing), seizures, uncontrolled rolling in the enclosure and death. Dragons that become infected as adults may suddenly die from neurological problems, but more often, they go on to develop liver disease and other health problems. Some baby and adult dragons appear to be resistant to infection, and some ADV-positive dragons may appear healthy but are carriers and shed the virus throughout their lives.
How it Spreads
It's important to understand that there are seemingly healthy bearded dragons that carry the atadenovirus, and they can spread it to uninfected dragons. If a male is a carrier, he can infect the females put in with him for breeding. If one of those infected females is placed with an uninfected male the next year, that male gets infected and can pass on the virus to other females, and so on. The virus is not spread by sexual contact alone, it can be passed just from sharing the same cage, which is why it spreads so quickly in baby dragons, leading to epidemics of unthriftiness and unexpected death. Atadenovirus may be passed from mothers to babies, and just a single ADV-positive baby can readily infect all of the other babies in the incubator or the baby cages.
Play it Safe
It is quite easy to end up with an infected colony if all of the adults are not carefully screened and managed to be sure they are ADV negative.
Diagnoses and Treatment
Your veterinarian's treatment plan will depend on what else may be wrong with your bearded dragon. A fecal parasite exam and bloodwork to assess the white blood cell numbers, detect anemia, and rule out changes in liver and kidney function may be done at the veterinary hospital. Tests to detect atadenovirus and other diseases have to be sent to an outside lab, such as the laboratory of Dr. Jim Wellehan, a leading researcher in reptile infectious diseases based at the University of Florida Veterinary Medical Teaching Hospital. Your veterinarian's recommendations are only as good as the diagnostic tests you allow to help him or her assess your dragon. If you decide to skip certain tests, your veterinarian will have more uncertainty about what is best for your dragon.
Unfortunately, there is no known drug that eliminates atadenovirus. An ill, ADV-positive bearded dragon needs to stay warm, have ultraviolet-B light and be kept by itself, so that it doesn't have to compete with healthy dragons for food and basking space. If it is dehydrated, your veterinarian may prescribe fluids to be given by injection, or simply a daily soak in shallow, lukewarm water or even drinking water placed into the mouth by a syringe. If it is losing weight, assist-feeding with crushed insects placed into the mouth may help. Highly digestible liquid diets and extra vitamins and calcium may be needed if the intestine has been damaged by infection to the point that the dragon is not able to absorb sufficient nutrition from its food. If a bacterial or fungal infection is detected, the veterinarian may prescribe antibiotics or antifungal medications. If the liver is not working properly, milk thistle and other nutriceuticals may be suggested.
Unfortunately, many baby dragons that are younger than 90 days old when they get infected with atadenovirus will die or become so sick that they need to be euthanized. Some infected dragons live normal lives and do not need much in the way of medical care. They are fine as pets but should be kept away from other dragons, other than those known to be ADV positive, too. Other dragons may have flare-ups and lose their appetite, sleep a lot, have diarrhea or constipation, and may even develop swellings of the belly or beneath the chin. Some dragons develop more serious signs later in life, from the virus spreading to the nervous system. There is no way to predict which dragons can do well with atadenovirus infection and which ones are going to have long-term health problems.
It is possible to manage breeding colonies so that the adults are free of atadenovirus and produce healthy uninfected babies. The first step is to test your bearded dragons and determine their status. An experienced veterinarian can collect samples to submit for laboratory testing. It may take seven to 14 days for test results. In the meantime, work out a plan for what steps you will take after the test.
Be very careful about how you manage your colony. Test all incoming dragons for atadenovirus and keep them isolated in a separate room from your uninfected dragons until the test results are reported. Service the new dragons last, after you are done working with your breeding group, and do not go back to handle any of your uninfected dragons after caring for those in quarantine.
If the new dragons have negative test results, it is not 100-percent certain that they are truly free of this disease. Continue to quarantine them for a total of 60 days and consider retesting them after the first 30 days, just to make sure that they are truly uninfected. If you notice any that are not doing well, retest them. If any are ADV positive on the first or second screening, they all should be considered contaminated and should not be brought into your ADV-free breeding colony. If there is one that you absolutely must keep that tested negative but was exposed to ADV-positive dragons, you may keep it isolated for six months and test it at 90 days and 120 days. That means no other dragons come into quarantine until it has completed this six-month process. If it tests negative both times during this six-month quarantine, then you may consider adding it to your breeding colony. However, there is still a very slight risk that this could introduce atadenovirus into your colony, so ask yourself again if this new breeder is really worth the risk.
If you're thinking about buying your first bearded dragon as a pet, be aware that many breeders do not test their dragons, so it can be difficult to find "clean" babies. Be prepared to pay more for babies from a clean colony backed up by testing through a reputable veterinarian and laboratory. Get your dragon tested for atadenovirus within the first week of bringing it home. If you discover that your dragon is infected, talk to your veterinarian and develop a lifelong preventive medicine plan.
If you already have bearded dragons, particularly if you are breeding them or planning to breed them, work with your local veterinarian to have them tested. If you have a large collection, you can group together swabs from all the dragons in a single cage rather than individually test them, and then any cages that are negative can be separated from the ADV-positive cages and retested later. What you do with ADV-positive dragons is a concern. I believe they can make good pets, but that the owners should be informed their new pets are ADV positive and what that means.
I recognize that it will be difficult to eliminate atadenovirus from bearded dragons. Some breeders believe that they are breeding resistance to the virus. Viral researchers suggest otherwise, citing cases where viruses adapt quickly to any improvements in animals' immune systems. The co-evolution of a virus and its host may result in a benign virus that causes minimal illness, or it may create more harmful strains, whichever best ensures that the virus survives and multiplies. Right now, atadenovirus is somewhere in the middle, causing serious illness in many dragons. Whether it is still in captive bearded dragon colonies 20 years from now will depend on what consumers demand and what breeders provide.
The author thanks Dr. Jim Wellehan for taking the time to be interviewed in the preparation of this article. REPTILES
Kevin Wright, DVM, is a Diplomate of the American Board of Veterinary Practitioners (Specialist in Reptiles and Amphibians) and works at the Arizona Exotic Animal Hospital, in Mesa, Ariz. The hospital website, www.azeah.com, includes more than 150 free articles on exotic pets. Dr. Wright and Dr. Johnson treat a wide variety of exotic pets.