Monthly Archives: May 2012

Ticks untold

Prime suspects in mystery fevers may hold new tick-borne diseases
Suddenly your horse is sick and you don’t know why. She breathes normally but her temperature is rising, her eyes grow yellow with jaundice, she seems depressed, and barely eats. The fever is clear but the cause is not; even the most experienced experts can offer no concrete answers. Eventually the fever fades, but is that the end of whatever caused it or is the source still lurking somewhere inside?

Horse owners across the states are facing this distressing scenario. At the Cornell University Animal Health Diagnostic Center (AHDC), Dr. Linda Mittel fields a growing number of calls about these mysterious fevers of unknown origins (FUOs). Many come from the Northeast, Mid-Atlantic, and Great Lakes areas: the nation’s topmost hotbeds of human tick-borne disease. This pattern led Mittel to suspect that the culprits of the fever caper could be ticks and the difficult-to-diagnose diseases they carry.

“Tick-borne diseases are some of the fastest growing emerging diseases in the United States right now,” said Mittel. “As ticks continue expanding their numbers and geographic range these diseases may affect new areas. We get calls about fevers at broodmare operations, showbarns, and farms where race horses rest or layup, even in areas where they didn’t know they had ticks. But horses moving between states can move ticks with them, and the effects of this movement are starting to show.”

Mittel and colleagues at the AHDC are embarking on a project to find just what diseases ticks in hotbed zones are carrying and whether they are behind the wash of mystery fevers in horses. The study will use samples from horses suffering FUOs to look for bacterial infections known to be transmitted by ticks (Anaplasma, Babesia, Borrelia, Ehrlichia, and Rickettsia) as well as other bacteria known to cause non-respiratory infection in horses (Leptospira, Bartonella, and Neorickettsia.)

These agents are considered emerging infectious diseases in humans, and this will be the first study determining their presence in horses with FUOs. The study will also sample ticks found on or near horses in designated areas to find which pathogens they carry and to potentially discover previously undocumented tick-borne pathogens.

Many tick-borne diseases are sensitive to specific drugs; others are not sensitive to antibiotics at all. Knowing which diseases are at the root of FUOs will help veterinarians treat them effectively. It will also help owners understand how the causes of fevers might impact affected horses’ futures in racing, performance, or showmanship.

“I’m quite excited to start solving the mysteries of these fevers and to possibly uncover new previously unrecognized diseases – in horses and people,” said Mittel. “If these agents are in the horses, humans may also have them without realizing– people who work with these horses might be particularly at risk. Knowing what we’re dealing with here will hopefully solve the mystery of FUOs and help equine and human medicine recognize and address the growing onslaught of tick-borne disease.”

This research is funded by the Harry M. Zweig Memorial Fund for Equine Research.

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Mike meets Minnie

Cornell University’s Hospital for Animals welcomes its newest resident: Minnie the miniature horse. Minnie’s stint at the hospital as a patient turned into a career as a companion when her owner generously donated her after learning the Hospital was seeking company for Mike, the College’s blood-donor draft-horse.

“Mike lived by himself, and horses are herd animals that do better in groups,” said Dr. Sally Ness, internal medicine resident.

Good timing is a great matchmaker, and despite the size difference the unlikely pair clicked. Minnie has also become a star attraction at the College’s Annual Open House, where she made her first public debut in April 2012 by popular request.

“Twenty kids lined up along the paddock fence asking to ‘pet the pony,’” said Ness. “Students spiffed her up with ribbons, and she was a huge hit. Mike loves his new pal and was actually a little concerned when we borrowed her for the festivities. They are fully moved in together and share his stall and paddock. She is definitely the boss:we were worried about Mike stealing her grain, but in fact she will finish and go over and push him away from his breakfast! But he seems to appreciate the company and doesn’t seem to mind.”

Dr. Cynthia Leifer honored with 2012 Pfizer Animal Health Award

LeiferDr. Cynthia Leifer, assistant professor of immunology at Cornell University’s College of Veterinary Medicine, has been selected to receive the Pfizer Animal Health Award for Veterinary Research Excellence. The award fosters innovative research by recognizing outstanding research and productivity from a faculty member early in his or her career. Nominees are selected for innovative research relevant to animal health that is likely to make national impact.

Leifer’s research sheds light on the currently cloudy causes of autoimmune disease by uncovering inner workings of the innate immune system. Afflicting one in five Americans, autoimmune diseases include a wide array of disorders from rheumatoid arthritis to the skin disease Lupus to irritable bowel syndrome.

“The immune system fights to protect us against invading microorganisms,” said Leifer. “But it must also recognize what to attack and keep its aggressive responses under control to prevent damaging our own bodies.”

When recognition and regulation fail, the immune system can attack the body and lead to autoimmune disorders. Leifer explores how immune cell receptors affect the way these cells recognize and respond to whatever they encounter, whether it’s a microbial invader or a piece of the self.

“Most innate immune receptors identify microbes by detecting unique structures found only on microbes,” said Leifer. “But some work by detecting structures present in both microbes and the self, such as DNA.”

Focusing her research on one such receptor, Toll-like receptor 9 (TLR9), Leifer recently discovered how TLR9 makes the kind of recognition mistakes that lead to autoimmune attacks, opening the door to new possible autoimmune disease therapies.

“Identifying immune-cell regulation systems may reveal therapeutic targets for managing TLR9 function, leading to new treatments for autoimmune diseases,” said Leifer.

Leifer will present her research at a special seminar to be held in September 2012. At a ceremony that follows she will receive an award of $1,000 and an engraved plaque.

“This is a great honor for Dr. Leifer at this stage of her career,” said Dr. Avery August, chair of the department of microbiology and immunology. “Her cutting-edge work on how the immune system senses pathogens is being recognized, and she will join a distinguished list of Cornell faculty who have received this award. We congratulate her on this great accomplishment.”

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College of Veterinary Medicine News
http://www.vet.cornell.edu/news/LeiferPfizer.cfm