Research Accomplishment Reports 2010

Biology, Ecology & Management of Emerging Disease Vectors

S.L. Dobson
Department of Entomology

 

Non-Technical Summary

Outputs:

Development of an integrated control strategy and specific recommendations for area-wide control of the Asian tiger mosquito.

Development of models that predict risk for key mosquito-borne diseases.

Assess the feasibility of initiating large field cage experiments on the sterile insect technique.

Outcomes or Projected Impacts:

An interactive and interdependent network of scientific expertise to deal with new mosquito-borne disease outbreaks.

Impact on the general public by understanding, assessing, and mitigating the threat posed by mosquitoes of public health importance.

Enhanced capacity to detect and predict outbreaks of vectors and associated diseases.

Provide for and encourage environmentally sound, scientifically based, and professional control by mosquito control agencies.

2010 Project Description

Approvals have been obtained, allowing for the open release of Ae. albopictus males in Kentucky. Initial field trials have tested Mark-Release-Recapture methods for assessing Ae. albopictus male dispersal and survival following a point release. Methods developed in Project Year 1 were trialed, including classical fluorescent dyes and molecular methods. One of the molecular methods was observed to show good persistence in the field with little fitness impact on treated males. A deficiency observed is the current inability to capture Ae. albopictus males. Collections were typically female biased (e.g. 61%, 56%) and less than 1% of the released males were recaptured, which complicates interpretation of the results.

In an effort to increase male recapture rates, future MRR experiments will include additional collection methods and tools. An aposymbiotic laboratory strain has been compared with a recently established, wild caught strain. No differences were observed in male performance, including competition for mates. Experimental values for percent hatching broods did not differ statistically with predicted values through three replications.

In anticipation of Wolbachia-based biopesticide experiments, a closed greenhouse mesocosm system has been developed for maintaining and monitoring closed populations of Aedes albopictus. Replicate populations were maintained and monitored for 50 days, recording eclosion rates, sex ratio, egg production and estimating hatch rates. The results support downstream large-scale experiments assessing proposed control strategies.

2010 Impact

Development of an integrated control strategy and specific recommendations for area-wide control of the Asian tiger mosquito.

Assess the feasibility of initiating large field cage experiments on the sterile insect technique.

Provide for and encourage environmentally sound, scientifically based, and professional control by mosquito control agencies.

2010 Publications

Gavotte, L., D. R. Mercer, J. J. Stoeckle, and S. L. Dobson. 2010. Costs and benefits of Wolbachia infection in immature Aedes albopictus depend upon sex and competition level. J. Invert. Path. 105: 341-346.

Fu, Y., L. Gavotte, D. R. Mercer, and S. L. Dobson. 2010. Artificial Triple Wolbachia Infection in Aedes albopictus Yields a New Pattern of Unidirectional Cytoplasmic Incompatibility. Appl. Environ. Microbiol. 76: 5887-5891.

Calvitti, M., R. Moretti, E. Lampazzi, R. Bellini, and S. L. Dobson. 2010. Characterization of a New Aedes albopictus (Diptera: Culicidae): Wolbachia pipientis (Rickettsiales: Rickettsiaceae) Symbiotic Association Generated by Artificial Transfer of the wPip Strain From Culex pipiens (Diptera: Culicidae). J. Med. Entomol. 47: 179-187.