Sunday, 17 April 2011

Animals as sentinels for disease

This week’s intellectual exchange featured guest lecturers Dr. Larry Glickman and Dr. William Stokes. Dr. Larry Glickman is a veterinarian and epidemiologist. He presented on some of his research on surveillance of companion animals as an indicator of disease. One case study he presented was on the transmission of Toxocara canis, or Dog Roundworm infection. The eggs of Toxocara are present in the environment and are extremely resilient, lasting for years without a host. Dogs are a natural host for Toxocara. By our exposure to dogs, people (especially young children), are at risk for acquiring the parasite. As humans are an unnatural host for Toxocara, we can experience debilitating symptoms as a result, including respiratory and eye health issues. Over twenty million children are infected at any one time. Although most cases are asymptomatic, 3000 cases of blindness are caused yearly due to the parasite traveling to the eye. In West Africa, Toxocara is also a serious issue. Due to the high prevalence of pica, or the consumption of earth, transmission of Toxocara is high. Dr. Glickman discussed further about using companion animals as sentinels for environmental exposure, and has constructed a novel database using a centralized medical records system which allows for the surveillance of animal diseases.

Dr. William Stokes, a Rear Admiral, veterinarian and Director of the U.S. National Toxicology Program’s Interagency Center for the Evaluation of Alternative Toxicological Methods (NICEATM) at the National Institute of Environmental Health Sciences (NIEHS), presented on the history of the United States Public Health Service Commissioned Corps. The Corps is an integrated group of veterinarians, physicians, and epidemiologists among other professions, and is one of seven uniformed services. It is tasked with the role of protecting, promoting, and advancing the health and safety of the nation. Dr. Stokes covered a variety of one health related issues that dealt specifically with the use of animals as sentinels for disease, and presented a unifying scientific framework for addressing environmental health hazards. Dr. Stokes noted that animals are particularly useful for surveillance because their exposures to environmental hazards may be greater than human exposures, resulting in development of adverse effects. Additionally, some species respond more quickly to environmental hazards due to increased susceptibility associated with shorter life spans, thus providing valuable information to the symptoms and consequences of environmental exposure. His presentation provided insight into how the U.S. Public Health Service Commissioned Corps integrates One Health concepts into national surveillance on environmental health.