American Veterinary Medical Frontiers has announced a breakthrough in the field of retroviral research with the confirmation of a successfully-bred horse with natural immunity to the deadly Equine Infectious Anemia Virus (EIA).
Dr. Robert J. Tashjian, an internationally-recognized expert in EIA, has announced the exciting finding, which is the culmination of his more than 40 years of research on the virus.
"This breakthrough adds an important component to the understanding of retroviruses, and may have implications for the understanding of Human Immunodeficiency Virus (HIV), the causative agent of AIDS," Dr. Tashjian said.
Lentiviruses are a class of retroviruses which damage the immune system of horses (EIA), simians (SIV), humans (HIV) and cats (FIV). In the 1970s, Dr. Tashjian observed that an EIA-positive herd of horses lived side by side with EIA-negative horses, without a statistical increase in mortality among the negative horses. Dr. Tashjian brought a small herd of seemingly resistant horses to West Boylston and started a breeding program. The intent of the breeding program was to amplify and document the natural immunity that he had observed anecdotally decades before. That natural immunity was recently confirmed when 'Nora' tested negative for EIA despite significant exposure to the virus.
The Division of Animal Health of the Massachusetts Division of Agricultural Resources, which had killed another AVMF research horse last year, has now ordered the destruction of this unique horse named Nora out of fear it may infect other horses. Per their prior order, Nora lives in quarantine on the Malden Brook Farm. She has lived a happy, disease-free life of 10 years.
Current USDA approved tests for EIA include the Coggins and ELISA tests. Nora has tested negative twice on both the Coggins and ELISA tests. A subsequent immunoblot test showed a minor immune response to the virus, which may reflect exposure. This test is not USDA approved as definitive for EIA exposure, nor is it predictive of disease.
Today, Nora is a healthy, well-cared-for, friendly horse. Nora represents an exciting opportunity in the field of virology. This is the first time that a horse has been bred for immunity to a retrovirus. In addition, Nora's destruction would be tragic, as she is disease-free.
"Dr. Tashjian, an international authority on EIA, began studying this infection many years ago when he was director of the New York Animal Medical Center," said Leonard J. Morse, MD, Commissioner of Public Health, City of Worcester Massachusetts. "The virus that causes EIA is closely related to the Human Immunodeficiency Virus (HIV), the cause of Acquired Immunodeficiency Syndrome (AIDS). I greatly respect the scientific contributions and accomplishments of Dr. Tashjian."
"Over the past 40 years, Dr. Tashjian, through his cutting-edge research, has become one of a very few internationally recognized experts in EIA," said Gregory R. Ciottone, MD, Assistant Professor of Medicine, Harvard Medical School. "His collaborative work has led to a number of breakthroughs in the understanding of this retrovirus. The culmination of this research is the idea that a vaccine for EIA, similar in structure and action to human HIV, may be possible. He has managed to discover, through relentless study, that a horse can be exposed to EIA, demonstrate that exposure, yet never manifest the disease. This naturally-developed immunity is instrumental to the development of a vaccine for this retroviral disease, and may lead to the creation of the same for HIV. The living model of this immunity is Nora, the very horse in question now."
(AVMF)