Permission to cross post the following information to other lists is granted, as long as the post is taken in it entirety, with out any changes or additions. When the research team at UGA started out, they determined that the tests that were currently available were not accurate enough and not specific enough for their purposes. They needed to do more than verify the presence of ADV. They needed tests that would qualitatively and quantitatively describe going on with the virus and the animal's body. And so, starting with the Counterimmuneoelectrophoresis (usually called CEP or CIEP) test, and working from there, they have worked with and developed several tests that will meet their needs. With the CEP test, they started reporting results using titers, rather than just reporting a positive or negative result. Titers give an idea of the concentration of the antibodies in the animal's blood stream. Titers are accomplished by a series of dilutions of the test sample with a non reactive substance, and testing until a negative result is received. For example, they would start with one part of the blood serum, and dilute it with 4 parts of saline, and test. If the result was positive, they would then use a dilution of 16, then 64, 256, 1024, etc. The amount of the dilution would increase in powers of 4. The higher the dilution needed to achieve a negative result, the greater the concentration of antibodies in the test sample. With studies that were previously done on mink, there was a correlation between the titer level and the health of the animal. Once the titer reached a certain level, the mink usually died within a few weeks. In both mink and ferrets, they consider dilutions of 4 and 16 to be low titers, 64 and 256 to be moderate titers, and 1024 and above are considered a high titer. What they found was that with ferrets the titer level was not a good way to judge the likelihood that the animal was nearing death from ADV. Many ferrets with high antibody titers went on to live several years with the titer remaining constant. Even though using titers with the CEP gives additional information that was not offered with commercial tests, it was still not enough. The CEP test is an antibody test. It verifies that the body has been exposed to the virus, and has created antibodies, but it does not prove that the virus is still there. So, a test for the actual virus, or antigen, was needed. One of the first tests they worked with after the CEP was the PCR, or polymerase chain reaction. The PCR test can be used to detect any kind of viral DNA in a sample, and yields a simple positive or negative result. The PCR is not used only for ADV, and in fact, there are now PCR tests for AIDS that are commercially available. The PCR test for ADV is usually run on a fluid sample. Initially, all of the blood samples they received from us from ferrets that had tested positive with United's CEP test tested positive for antibodies, but were negative for antigen. This did not mean that the ferrets that were providing samples did not have the virus, just that it was not present in their fluids. With ADV, often the virus settles in the organs. When this happens, the ferret is not in a contagious state, because unless his organs are eaten by another animal, there is no way for the virus to move to another animal. But sometimes, in some ferrets, the virus moves into the bodily fluids, and can then be transmitted through the fluids to other ferrets. When a ferret's blood, saliva, feces or urine tests positive with a PCR test, then that ferret can transmit ADV to other animals. The PCR test could be very useful to ferret owners if it could be run in their vet's office, because it would let them know if a ferret that was ADV+ was contagious at that moment in time. Unfortunately, it is unlikely this will happen in the near future. To run it requires very expensive equipment, and a highly trained technician who is familiar with the procedure. Some of the commercial labs may decide to offer the test, but since there would be a lag time in getting the results, it may lose some of its meaning. The test would only tell you what was occurring at the time the sample was taken, and while it is unlikely the status changes rapidly (like overnight), it is possible. So, the PCR test is something that is more useful from just the research standpoint. It is important to remember that a negative PCR test does not mean a ferret does not have ADV, just that the virus is not present in the fluids at that time. A positive result is a conclusive proof that the ferret has ADV, though One test that the U of GA developed, and has made commercially available is the DNA in situ hybridization test. This is a test run on tissue samples taken either during necropsy or biopsy of organs, and is extremely accurate. Again, this test can be set up to find a number of different viruses. But, UGA has modified it to use in identifying ADV viral particles. This test is very valuable to the research team, because it highlights where the virus is in the tissue samples, making it easier for them to study. From a diagnostic standpoint (or from the ferret owner's point of view), it is an extremely accurate test that will let them know for certain whether or not a ferret has ADV. However, because it requires a tissue sample, it is not a good starting point for testing. Finally, the UGA team has been perfecting an ELISA test for ADV. ELISA is an abbreviation for "enzyme-linked immunosorbent assay". ELISA tests are widely utilized to detect substances that have antigenic properties, primarily proteins (as opposed to small molecules and ions such as glucose and potassium). The substances detected by ELISA tests include hormones, bacterial antigens and antibodies. The ELISA test that UGA has developed for ADV will give a result expressed in titers (actual numbers, not just low or high). It will not be the same as the ELISA test offered by Avecon Diagnostics. The Avecon ELISA is an antibody test. I do not know enough about the UGA ELISA to say whether it will test for antibodies or antigen. While they have developed this test primarily for use in their research, they may be making this test commercially available in the near future, as they feel it will provide veterinary professionals with another highly accurate test to detect ADV. Developing these tests and insuring their accuracy was an important first step in the process, and was necessary before any other steps were taken. During this time, the team was accepting samples from ferrets from members of the ferret community. This was beneficial to both parties. The team had samples without having to infect more ferrets with ADV, and the owners who provided the samples got free testing. Now that the test development stage is over, the tests that are useful to vets and owners will be offered commercially. This also benefits the program, because it brings in money to cover expenses, freeing up the money that gets donated to cover the next phase of the research. I am certain that many people who donate do not want to think their funds are being used just to provide free testing to some individuals. But, the ferret owners who did provide samples during these early years should all be thanked. I only know a few of the names, and know there are many more who I don't know by name, so I will not try to pinpoint who these owners are. But, without their willingness to help, some ferrets would have had to be deliberately infected with ADV. Fortunately, to date, that has not had to happen. When I post again, I will talk some more about where the research currently stands. I may take a break for a day or two, though. -- Danee International Ferret Congress Health Issues Coordinator http://ferretcongress.org ADV - If your ferret hasn't been tested, you don't know! For more information visit: http://www.ferretadv.com You can help fight ADV! Visit: http://help4adv.terrabox.com/ [Posted in FML issue 4904]