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 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 Google Scholar Google Scholar Articles by Ksiazek, T. G. Articles by Reeves, W. C. Search for Related Content PubMed PubMed Citation Articles by Ksiazek, T. G. Articles by Reeves, W. C.

Effect of Normal Mosquito Extracts upon Arbovirus Recoveries from Mosquito Pools^*

Titers of Turlock (TUR) and Hart Park (HP) viruses were reduced to undetectable levels when virus was mixed with a triturated suspension of uninfected (normal) 4th instar larvae of Culex tarsalis prior to plaque assay in cell culture. There was a linear relationship between the number of larvae in the pool and the titer of virus recoverable. Virus was undetectable when 1,000–10,000 PFU of either agent was added to pools that contained 25 or more larvae. Suspensions of up to 25 adult male or female Cx. tarsalis had little effect on detectable viral titers while pupal suspensions had an intermediate effect. The inhibitory effect of normal larval extracts on viral infectivity could be counteracted by use of polycations or a high pH buffer. A similar reduction in titer of TUR virus was observed with extracts of larvae of Aedes melanimon or Anopheles franciscanus. Larval extracts of Cx. tarsalis similarly reduced titers of California and St. Louis encephalitis viruses but not western equine encephalomyelitis virus. These findings may have significant bearing on the interpretation of transovarial transmission attempts in which pooled larvae are assayed for virus.

Accepted for publication November 23, 1984.

^* This study was supported in part by funds from the National Institute of Allergy and Infectious Diseases (Research Grant AI 003028); the U.S. Army Medical Research and Development Command (Contract No. DAMD 17-77-C-7018); the Office of Naval Research, Microbiology Program, Naval Biology Project (Contract N0014-81-C0570, NR205-001); and by special funds for mosquito control research appropriated annually by the California State Legislature. The senior author was supported in part by the Air Force Institute of Technology.

¹ Current address: U.S. Army Medical Research Institute of Infectious Diseases, Ft. Detrick, Maryland 21701.

Address reprint requests to: Dr. James L. Hardy, School of Public Health, 216 Earl Warren Hall, University of California, Berkeley, California 94720.