Newswise — Human, animal, and environmental are not three different kinds of health. They are One Health.

One Health is the overarching concept that human, animal, and environmental health are inextricably linked and that professionals within the three realms should work together toward research findings and clinical applications that can improve the health in all three areas. 

The Virginia-Maryland College of Veterinary Medicine — both throughout its public health program and more traditional veterinary medicine — is committed to the concept of One Health.

“Our college is strategically focused on improving One Health — the critically dynamic, interconnected, and interdependent health of people, animals, and the environment,” said M. Daniel Givens, dean of the veterinary college. “This improvement of One Health is the unifying foundation from which we initiate efforts across the college to advance applied veterinary medicine, biomedical science, and public health.”

One Health finds its most direct expression in the Center for One Health Research, a collaborative effort between the veterinary college and the Edward Via College of Osteopathic Medicine, a private, nonprofit medical school in Blacksburg.

“I'm a veterinarian, but I study human diseases,” said Mohamed Seleem Ph.D. ’06, the center's director. “Neisseria gonorrhea, for instance, does not infect animals at all, it just infects humans.”

Seleem, the Tyler J. and Francis F. Young Chair in Bacteriology, returned to Virginia Tech to lead the center in 2021 after nearly a decade at Purdue University. Much of his lab’s research has focused on repurposing existing drugs for treatment of diseases, such as gonorrhea and Candida auris, that either lack vaccines or have had prior pharmaceutical treatments be rendered less effective over time.

Seleem said veterinarians by training enter their careers with a philosophy that aligns with the goals of One Health. The veterinarians’ oath already includes “the promotion of public health” and “the advancement of medical knowledge” as chief planks, in addition to animal welfare.

“It’s easy for us working with animals that we already have set in our minds that human health is important,” Seleem said. “So when we work with animals and we want to really address the animal health, we already have in mind human health.”

The COVID-19 pandemic has highlighted how diseases originating in animals can cross over to humans through the environment and lead to dire impacts on society.

“A microorganism that’s causing a problem in humans, it didn’t necessarily start in humans,” Seleem said. “It could have started in the environment, or started in the animal and gone through the environment and then to humans. So to address this and to prevent the illness or find a cure, we cannot just focus on one aspect of the problem, which is the human, and leave behind the environment and the animal.”

Global climate change is already proving to be an environmental factor that is exacerbating some diseases.

“The rise of Candida auris, a fungal infection first discovered in humans in 2009, is an example of the environment playing a major role in the spread of disease,” said Seleem, explaining that climate change has likely enabled the pathogen, which has adapted to warmer, more humid conditions, to proliferate and infect humans more often.

While Seleem is a veterinarian studying human diseases, X.J. Meng’s educational background is in human medicine, but he studies emerging and zoonotic animal viral diseases.

“There are a large number of pathogens circulating in a large number of animal species,” said Meng, University Distinguished Professor of Molecular Virology at the veterinary college and professor of internal medicine at the Virginia Tech Carilion School of Medicine. “We simply just don’t have the resources to study all these animal pathogens, and consequently the biology and pathogenic potential for many of these animal pathogens are not understood. However, these neglected animal pathogens are continuing to evolve and adapt in animal species and some could one day jump species and may infect humans. 

“The majority of emerging infectious diseases in humans came from animals.  My philosophy, and I’ve tried to convince whoever I can, is that the most cost-effective way to prevent emerging human infections is to stop the so-called animal pathogens in their own animal hosts before they can jump species and infect humans.”

Formerly known as the Center for Molecular Medicine and Infectious Diseases, the Center for One Health Research’s most historic achievement was the development of the RB51 brucellosis vaccine, approved in the 1990s as the official brucellosis vaccine of the U.S. Department of Agriculture and still in use in many nations abroad where the disease has not yet been fully controlled in livestock.

“For decades, the college’s Center for One Health Research has focused on innovative undertakings involving exclusive expertise to advance One Health through unique discoveries in the intricacies of disease pathways and the development of methods and tools to prevent and mitigate disease in animals and people,” Givens said.

Much groundbreaking research is ongoing at the center, including the following:

  • Jessica Gilbertie's lab has made a breakthrough discovery in the treatment of musculoskeletal injuries in horses. BIO-PLY combines naturally derived factors extracted from blood cells known as platelets, harnessing potent anti-inflammatory properties along with unique regenerative capabilities to address what were once considered terminal injuries in horses. Clinical trials are scheduled to start in 2024. 

  • Research led by Raj Gaji delves into the intricate host-pathogen interactions involving toxoplasma, a prime example of a One Health disease agent, passing from animal to human through undercooked meat or contact with feces. Gaji's lab recently unveiled the discovery of TgTKL4, a cell cycle-regulated kinase within the TKL family, that plays a pivotal role in the parasite's growth. The absence of the kinase compromises the parasite’s replication and invasion capabilities, shedding light on potential ways to fight the disease. 

  • Clayton Caswell's laboratory is uncovering critical genetic pathways essential for the intracellular survival and pathogenicity of Brucella, an agent responsible for debilitating human diseases and designated as a Select Agent because of its bioweapon potential. This groundbreaking work by the Caswell group promises to unveil novel pathways within Brucella, potentially opening doors for targeted vaccine and therapeutic development. 

  • Erin Gloag employs multidisciplinary strategies to unravel the mechanisms that enable pathogenic bacterial biofilms to persist within a host and establish chronic infections. The most recent breakthrough from Gloag's lab promises to shed new light on how the physical properties of biofilms promote persistence during infection by providing increased resistance to mechanical and chemical forms of clearance during lung infections. Gloag was awarded a Cystic Fibrosis Foundation Research Grant to pursue this research.

  • Blaise Costa’s lab has focused on a crucial component known as the N-methyl-D-aspartate (NMDA) receptor in the mammalian central nervous system. Proper functioning of the NMDA receptor is vital for higher-order brain functions like cognition and decision-making. Dysregulation of this receptor is associated with various neurological and psychiatric disorders. Costa’s Lab is actively identifying drug-like compounds that can modulate NMDA receptors, holding promise for the development of potential drug candidates to address neurological disorders.