id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-260554-nao59qx4	Wargo, Andrew R	Viral fitness: definitions, measurement, and current insights	2012-09-15		.txt	text/plain	2898	134	38	Important recent trends include increasing use of in vivo systems to assess vertebrate virus fitness, and a broadening of research beyond replicative fitness to also investigate transmission fitness and epidemiologic fitness. The majority of viral fitness study systems are based on RNA viruses, and the highest numbers of publications in recent years involves human pathogens associated with major disease emergence events, such as human immunodeficiency virus-1 (HIV-1), influenza virus, and dengue virus (DENV). In many cases the ultimate goal of replicative and transmission fitness studies is to understand the epidemiology 540 Virus evolution and population level processes governing viral evolution, emergence, and displacement in the field. For vertebrate viruses the recent increase of in vivo virus fitness research is encouraging, but the majority of studies still remain in vitro.	./cache/cord-260554-nao59qx4.txt	./txt/cord-260554-nao59qx4.txt