Experimental infection of Aedes sollicitans and Aedes taeniorhynchus with two chimeric Sindbis/Eastern equine encephalitis virus vaccine candidates.
Two chimeric vaccine candidates for Eastern equine encephalitis virus (EEEV) were developed by inserting the structural protein genes of either a North American (NA) or South American (SA) EEEV into a Sindbis virus (SINV) backbone. To assess the effect of chimerization on mosquito infectivity, experimental infections of two potential North American bridge vectors of EEEV, Aedes sollicitans and Ae. taeniorhynchus, were attempted. Both species were susceptible to oral infection with all viruses after ingestion of high titer blood meals of ca. 7.0 log(10) plaque-forming units/mL. Dissemination rates for SIN/NAEEEV (0 of 56) and SIN/SAEEEV (1 of 54) were low in Ae. taeniorhynchus and no evidence of transmission potential was observed. In contrast, the chimeras disseminated more efficiently in Ae. sollicitans (19 of 68 and 13 of 57, respectively) and were occasionally detected in the saliva of this species. These results indicate that chimerization of the vaccine candidates reduces infectivity. However, its impact on dissemination and potential transmission is mosquito species-specific.
Arrigo
Nicole C
NC
Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555, USA. ncarrigo@utmb.edu
Watts
Douglas M
DM
Frolov
Ilya
I
Weaver
Scott C
SC
D000330:Aedes / Q000821:virology*; D000818:Animals; D002678:Chimera; D004666:Encephalitis Virus, Venezuelan Equine / Q000235:genetics*; D004685:Encephalomyelitis, Venezuelan Equine / Q000635:transmission* / Q000821:virology; D005260:Female; D007303:Insect Vectors / Q000821:virology*; D012845:Sindbis Virus / Q000235:genetics*; D014614:Vaccines, Synthetic; D014765:Viral Vaccines
D014614:Vaccines, Synthetic; D014765:Viral Vaccines