id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-324953-3sacf4wu	Childs, James E.	Introduction: Conceptualizing and Partitioning the Emergence Process of Zoonotic Viruses from Wildlife to Humans	2007		.txt	text/plain	9017	379	40	The process of zoonotic disease emergence can be understood by coupling knowledge of how zoonotic viruses have evolved and are maintained among their wildlife hosts, transmitted across a species barrier to cause productive infection in a taxonomically distinct secondary host, initiate a pathologic process causing disease, and, by repetitive infection within the secondary host species, result in incident morbidity or mortality of sufficient magnitude to be detected and characterized as a novel health concern of local, regional, or global significance (see the chapter by Childs, this volume). The ecologic process of zoonotic disease emergence can be schematized by four transition stages (Fig. 1 ) , of which only the first two are prerequisites for emergence: (1) contact between infectious propagules originating from the wildlife H R with individuals of a susceptible H S and (2) cross-species transmission, a transition subsuming the complex interactions of the virus infectious cycle within the H S (Nayak 2000; Childs 2004 ).	./cache/cord-324953-3sacf4wu.txt	./txt/cord-324953-3sacf4wu.txt