Dr. Peter Schantz, speaker from CDC, talks with students.
A long, long time ago, there was one type of doctor for all creatures, treating people and animals with whatever knowledge and resources were available. Over the years, medicine split into human and veterinary medicine, and since that time the specialized branches have grown. There will always be a need for specialization, but what may have been lost in the process is the interrelationship and commonalities of human and animal medicine that can help both medical professions.
With this idea in mind, the Virginia-Maryland Regional College of Veterinary Medicine in October hosted a symposium, "The Bridge Between Veterinary Medicine and Human Health," the second in a series designed to educate doctors on both sides of the fence. The symposium, sponsored by the Virginia-Maryland Regional College of Veterinary Medicine, the Medical College of Virginia at Virginia Commonwealth University, Virginia VMA, Maryland VMA, Merial, and Hill's Pet Products, focused on the risks of animal interactions to human health and well-being. The overall emphasis was on zoonosis and medicine, but other issues—legal, psychologic, and ethical, among them all became part of the total picture by the time the sun went down over the hills of Blacksburg, Va.
Dr. Peter Eyre, dean at Virginia-Maryland, welcomed the audience, consisting largely of veterinarians but including many physicians. "We've known for generations that companion animals have beneficial effects on human health and well-being," he said, "but we haven't understood very much about why that is so, and how veterinary medicine and human medicine merge together."
Following this introduction, Dr. Jorge Guerrero, executive director of professional services for Merial and adjunct professor of veterinary parasitology at the University of Pennsylvania School of Veterinary Medicine, set the stage for the day with his talk "One Medicine." Approaching the topic from a pharmacologic perspective, he gave examples of drugs that were developed for use in animals and later had human applications, then gave examples of the reverse being true.
He used ivermectin as a prime example. Dr. Guerrero said it was adapted for use in humans in the late 1980s after seven years of continuous use in animals. He also spoke about a drug used for peptic ulcers in humans that was later used to treat equine gastric ulcer syndrome. Lyme disease vaccine and enalapril maleate were among the other biologics and drugs he cited as having vital applications for humans and animals.
"The benefits of these interrelationships are multiple, and both fields of medicine have much to gain and learn from each other," Dr. Guerrero said.
In the first of many speakers' talks about zoonoses and public health, Dr. Peter Schantz, epidemiologist from the division of parasitic diseases at the National Center for Infectious Diseases, CDC, offered his insights about the zoonotic risks of intestinal parasites of dogs and cats, and strategies for preventing them. His work with the CDC involves many issues common to veterinary and human medicine.
"We have more veterinarians working at CDC than at any other time in its history," Dr. Schantz said. "The role of the veterinarian in public health has become widely appreciated, and I think there are unlimited opportunities for veterinarians today exploring those particular areas."
He said that many people are not properly informed about the human health risks associated with animal interaction. Dr. Schantz cited a survey he conducted of 149 heads of households which revealed that a low proportion of them were aware that pet diseases (other than rabies) could be transferred to humans.
The second half of Dr. Schantz's talk was on leishmaniasis, a disease that has plagued Foxhounds in the United States and continues to persist, with many questions still unanswered. He suggested that perhaps the nature and management of the Foxhound breed has been a factor in transmission. "Most Foxhounds are kenneled together, they're involved in national and regional competitions, and there's drafting of hounds from one hunt to another. ("There is also a recent report of visceral leishmaniasis in a Poodle in Maryland, from an as yet undetermined source. See JAVMA, Dec 1, 2000, page 1686 for details.)
Dr. Leonard Marcus, whose background includes more than 30 years in tropical medicine and vector-borne diseases, talked about bite-associated zoonoses. His discussion of the incidence of rabies spanned the past 50 years and looked at the species involved and the geographic distribution of the disease.
Commenting on the efficacy of rabies vaccine, Dr. Marcus said education and awareness are vital. "Both the physician and the veterinarian ought to be involved in preventing animal bites." He lauded the AVMA for its bite prevention campaign.
Dr. Phyllis Cassano, a manager of veterinary professional services for Merial, presented a review of zoonoses in the 21st century.
"Veterinarians have always been in the forefront in combating zoonotic diseases," she said, citing examples in which veterinarians were the first to discover disease, such as brucellosis and West Nile encephalitis. Dr. Cassano also presented a comprehensive talk about ticks—the types, history of their impact on health, and methods of preventing tick-related zoonoses.
"The same ticks that can transmit diseases to your pet can transmit diseases to your client," she reminded the audience. "Our professions know a lot about these diseases individually, but we have to link up and reinforce the bond between physicians and veterinarians."
A portion of Dr. Cassano's talk dealt with how zoonoses affect immunocompromised patients, another issue relevant to physicians and veterinarians. "We must be aware that parasitic zoonoses can be especially dangerous for patients with compromised immune systems who may be using pet-facilitated therapy," she said, while maintaining that pet interaction is intrinsically valuable to patients.
In her presentation, Sandra Barker, PhD, associate professor of psychiatry at the Medical College of Virginia at Virginia Commonwealth University and director of its psychiatric human-animal bond programs, said that research conducted in the past decade on the risks and benefits of patients with compromised immune systems interacting with pets is encouraging.
"The US Public Health Service concludes that pets present only minimal risk to immunocompromised persons," she said. Dr. Barker talked about the strength of the human-animal bond and how great a therapeutic factor this is to patients, mentally and physically. For pet therapy programs to be successful, she said that physicians and veterinarians need to educate patients on preventive measures to combat zoonoses. "The benefits outweigh the risks," she said. "Prohibition of pet ownership by individuals infected with HIV is not warranted."
Dr. Mark Haines, animal program director at the National Institutes of Health Clinical Center, continued in a similar vein when he talked about utilizing service animals in human hospitals. Presenting a slide show, he demonstrated the benefits of animal interaction with children and adult patients, emphasizing once again that the benefits merit efforts to encourage the programs and minimize the risks. By identifying and quantifying risks, Dr. Haines believes things can run smoothly. "The risk of zoonoses in our [NIH] hospital is very minimal," he said. "In 10 years of animals visiting the NIH Clinical Center, there has never been a disease problem from a visiting animal."
In the closing presentation, "Children, Pets, and Pests: The realities and myths of zoonotic diseases," Kevin Connelly, PhD, gave his perspectives on pets from the human medicine point of view. Dr. Connelly is assistant professor of pediatrics at Virginia Commonwealth Universities and director of the Paws for Health pet visitation program at the Children's Medical Center at Medical College of Virginia Hospitals.
Dr. Connelly said the typical physician doesn't inform clients of the risks of zoonoses. "They don't get proper training in zoonoses and think 'that's for veterinarians.'" He believes more communication between the disciplines is needed.
The moderator for the symposium, Dr. Marie Suthers-McCabe, associate professor of human-companion animal interaction at Virginia-Maryland, wrapped up the day appropriately. She announced the establishment of a joint academic center for the study of the animal-human interface between the Virginia-Maryland Regional College of Veterinary Medicine and the Medical College of Virginia at Virginia Commonwealth University. It's been dubbed CENTAUR, the Center for Animal Human Relationships.
Dr. Suthers-McCabe said, "We want to promote the collaboration between the human and veterinary medical communities through research, education, and service."