Figure 3.

Transmission routes to humans and animals^a,^b

^aAiello SE, editor. The Merck veterinary manual. 8th ed. Whitehouse Station (NJ): Merck – Co., Inc.; 1998.

^bThe Center for Food Security and Public Health. Iowa State University. Transmission routes [cited 2005 Nov 7]. Available from: URL: http://www.cfsph.iastate.edu/Handouts/resources_list.htm

^cPossible, depending on species