"One Medicine" for Animal and Human Health

2270 Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 10, No. 12, December 2004 tapped into the universal wish for harmony and peace. Well ahead of his time, he invited to his kingdoms not only leading human figures and innocent children but also a consortium of animals whose presence he found indispensable. Domesticated animals, part of his life as a farmer, appeared in realistic detail, but wild beasts were more idealized and decorative. In The Peaceable Kingdom on this month’s cover of Emerging Infectious Diseases, Hicks once more assembled the world’s creatures for an idyllic group portrait. Against a lighted backdrop of trees and river banks, animals and children gathered in the foreground. In mid-panel, leading Quaker William Penn concluded a peace treaty with the Lenni Lenape tribe. The colors were solid, the light well focused, and the curves of animal frames and horns gracefully outlined. Yet, Hicks was not denying tensions in the universe. The animals, whose anthropomorphic features betrayed human emotions, seemed puzzled and apprehensive. Even as the bull offered the lion hay, the king of beasts seemed stiff and uneasy. Even as the lamb cuddled up, the wolf wore a noncommittal glare. The world’s creatures may have been tamed, but peace in the scene seems precarious. The connectivity that Hicks sensed between humans, animals, and the universe was greater than the artist could have imagined. The intensity in the animals’ eyes was not the only troubling element in the picture. In the dander and under their breath, in the soil and in the water, on the leaves and the clothing of the dignitaries, lay creatures unknown to Hicks, microorganisms, insidiously moving from animals to humans, eating, multiplying, sharing, spreading, connecting. Even if Hicks could have arranged a perfectly peaceable kingdom, strife would have continued beneath the surface through the transmission of disease. Not long after Hicks’ death in 1849, German pathologist Rudolf Virchow (1821–1902) coined the term zoonosis, verifying the essential link between animal and human health (5). This link, further complicated by the emerging nature of disease and the ethical, ecologic, social, and economic values placed on the relation between humans and their pets, livestock, or fellow inhabitants of nature, has not been uniformly acknowledged or exploited—even in the face of AIDS, Ebola, West Nile virus, avian influenza, bovine spongiform encephalopathy, and SARS. In the 1980s, American epidemiologist Calvin Schwabe proposed a unified human and veterinary approach against zoonotic diseases. This approach, “one medicine” (6), upholds Virchow’s principles and affirms Hicks’ wish for the control of subversive elements, whether they interfere with harmonious animal and human interaction or they disrupt animal and human health.