HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Jahrling, P. B. Search for Related Content PubMed PubMed Citation Articles by Jahrling, P. B. Agricola Articles by Jahrling, P. B.

Virulence Heterogeneity of a Predominantly Avirulent Western Equine Encephalitis Virus Population

U.S. Army Medical Research Institute of Infectious Diseases Fort Detrick, Frederick, Maryland 21701

Selective removal of small plaque (SP) Western equine encephalitis (WEE) virus from a population heterogeneous with respect to virulence and plaque morphology permitted direct detection of a small sub-population of virulent large plaque (LP) WEE virus. Selective removal of SP-WEE virus was achieved by intracardiac (i.c.a.) inoculation of hamsters; plasma obtained 60 min after inoculation was proportionately enriched for LP-WEE virus since only the SP-WEE virus was cleared. By this method, the proportion of LP- to SP-WEE virus, in a population of SP-WEE virus which appeared to be homogeneous by conventional plaquing methods, was calculated to be 1 LP- to 250000 SP-WEE virions. The presence of a virulent LP-WEE virus sub-population explains why a single passage of a high but not low dose of SP-WEE virus in hamsters resulted in the emergence of an LP-WEE virus population with enhanced virulence.

Received 11 December 1975; accepted 9 March 1976.

This article has been cited by other articles:

				I. P. GREENE, S. PAESSLER, M. ANISHCHENKO, D. R. SMITH, A. C. BRAULT, I. FROLOV, and S. C. WEAVER VENEZUELAN EQUINE ENCEPHALITIS VIRUS IN THE GUINEA PIG MODEL: EVIDENCE FOR EPIZOOTIC VIRULENCE DETERMINANTS OUTSIDE THE E2 ENVELOPE GLYCOPROTEIN GENE Am J Trop Med Hyg, March 1, 2005; 72(3): 330 - 338. [Abstract] [Full Text] [PDF]

				A. P. Byrnes and D. E. Griffin Large-Plaque Mutants of Sindbis Virus Show Reduced Binding to Heparan Sulfate, Heightened Viremia, and Slower Clearance from the Circulation J. Virol., January 1, 2000; 74(2): 644 - 651. [Abstract] [Full Text]

				A. P. Byrnes and D. E. Griffin Binding of Sindbis Virus to Cell Surface Heparan Sulfate J. Virol., September 1, 1998; 72(9): 7349 - 7356. [Abstract] [Full Text] [PDF]