The contributions of Jagarlamudi et al1 and Bergamo2 to this issue of Infectious Diseases in Clinical Practice remind us of the health risks shared by human and nonhuman animal species. This human-animal-ecosystem interface has been described by the World Health Organization (WHO) as a continuum of direct or indirect human exposure to animals, their products, and their environments.3 In this continuum of exposure then, it should come as no surprise that animals may act as sentinel species for human disease1,4 or that another human may act as a sentinel species for another’s zoonotic disease after common animal exposure.2 Health care providers, both human and veterinary, are responsible for the historical exploration and the detailed unmasking of these complicated species interfaces. Such clinical discovery often requires a painstakingly detailed history of “pets, or travel, or dietary habits, or sexual escapades, or home improvement projects, or assorted hobbies” by an inquiring oftentimes obsessive-compulsive physician!5 The result of human-animal-ecosystem interactions and the subsequent historical connections made to these interactions by an inquiring physician is usually an “interesting case”—a case presented as an idiosyncrasy when it may only be the tip of the zoonotic iceberg. Given the constant human-animal-ecosystem exposures of numerous individuals throughout their daily activities with domestic animals, wild animals, animal vectors, animals foods, and even animal palliative care,6,7 it is probably surprising that more such zoonotic disease is not diagnosed on a routine basis.
Emerging and reemerging diseases most commonly arise from animal sources as has occurred with HIV infection, influenza variants, severe acute respiratory syndrome, and others.8 In the case of human pulmonary cryptococcosis reported in this issue of IDCP,1 the patient’s pet cat was a harbinger of human disease, and both animal and owner probably contracted cryptococcosis from environmental exposure to pigeon excreta from a pigeon roost surrounding the patient’s (and patient’s cat’s) porch. In Bergamo’s report of siblings with disseminated cat scratch disease (CSD) in this issue, the first sibling acted as a diagnostic harbinger of illness for the second sibling with hepatosplenic disseminated cat scratch disease, and both had exposure to the family’s kitten—the face of the younger sibling having been licked by the kitten!2
After 34 years of experience in the field of clinical infectious diseases, I am still awed by the diagnostic pearls uncovered by a careful, tedious, detailed, ongoing, and personalized medical history as demonstrated by these current and other case reports.1,2,5,7 The world is an interactive environmental wonderland, and only when we as physicians realize the vast nature of the human-animal-ecosystem interface will we more quickly discover the benefits of using detailed histories and shared zoonotic disease information to both patients’ and animals’ benefits. The WHO3,6 and the One Health Initiative8 have recognized the need for professional and multidisciplinary cooperation and collaboration among physicians, veterinarians, dentists, nurses, microbiologists, immunologists, environmental scientists, and ecosystem specialists throughout the world. As the global burden of zoonotic infection expands9–11 and as we continuously teach ourselves to routinely probe the historical harbingers of zoonotic disease processes,1,2,4 we will find greater need and benefit to partner with our many colleagues from the fields of veterinary medicine, dentistry, microbiology, immunology, and environmental/ecosystem sciences to diagnose and prevent such diseases. We face “The Perpetual Challenge of Infectious Diseases”11—we can stand stronger and longer as we ally with all members of the ecosystem’s medical team in a joint and collaborative effort to benefit human, animal, and ecosystem health care initiatives.3,6,8
1. Jagarlamudi R, Malani AN. Cryptococcosis: the owner and his cat. Infect Dis Clin Pract. 2012;Current.
2. Bergamo DF. Disseminated cat scratch disease, “A tail of two sisters.” Infect Dis Clin Pract. 2012;Current.
4. Sarosi GA, Eckman MR, Davies SF, et al.. Canine blastomycosis as a harbinger of human disease. Ann Intern Med. 1979; 91 (5): 733–735.
7. Myers EM, Ward SL, Myers JP. Life-threatening respiratory pasteurellosis associated with palliative pet care. Clin Infect Dis. 2012; 54 (6): e55–e57.
9. Burke RL, Kronmann KC, Daniels CC, et al.. A review of zoonotic disease surveillance supported by the Armed Forces Health Surveillance Center. Zoonoses Public Health. 2012; 59 (3): 164–175.
10. Christou L. The global burden of bacterial and viral zoonotic infections. Clin Microbiol Infect. 2011; 17 (3): 326–330.
11. Fauci AS, Morens DM. The perpetual challenge of infectious diseases. N Engl J Med. 2012; 366 (5): 454–461.