Evaluation of pyriproxyfen dissemination via Aedes albopictus (Skuse) from a point source larvicide application in Northeast Florida

Authors: LLOYD, AARON - Pasco County Mosquito Control; FAROOQ, MUHAMMAD - Navy And Marine Corps Public Health Center (NMCPHC); ESTEP, ALDEN - Navy And Marine Corps Public Health Center (NMCPHC); XUE, RUI-DE - Anastasia Mosquito Control District; Kline, Daniel - Dan

Submitted to: Journal of the American Mosquito Control Association
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/4/2016
Publication Date: 6/5/2017
Citation: Lloyd, A.M., Farooq, M., Estep, A.S., Xue, R., Kline, D.L. 2017. Evaluation of pyriproxyfen dissemination via Aedes albopictus (Skuse) from a point source larvicide application in Northeast Florida. Journal of the American Mosquito Control Association. 33(2):151-155. doi:10.2987/14-6459.1.
DOI: https://doi.org/10.2987/14-6459.1

Interpretive Summary: This was a collaborative project between scientists from the USDA Center for Medical, Agricultural, and Veterinary Entomology (CMAVE), U.S. Navy Entomology Center of Excellence (NECE) and Anastasia Mosquito Control District (AMCD). The Asian tiger mosquito, Aedes albopictus (Skuse), ranks among the most significant vectors of dengue fever and chikungunya virus. Standard mosquito control measures utilizing adulticides and larvicides are not ideal to manage Ae. albopictus populations. Therefore, this collaborative project was developed to evaluate a novel approach for the control of this invasive mosquito species. This study evaluated the autodissemination technique for the dissemination of the insect growth regulator NyGuard® (pyriproxyfen) that was applied as a point source treatment to a tire pile from a ULV back pack sprayer to sites ca. 400 meters from the treatment site. Results from this study indicate that pyriproxyfen is an effective larvacide for 4 to 5 weeks against Ae. albopictus larvae. However, pyriproxyfen does not seem to disseminate well via mosquito when formulated as a liquid and applied from a back pack ULV sprayer. Prior studies reported success with autodisemmination of pyriproxyfen when using a dust formulation; therefore, further evaluation is needed to identify additional formulations and techniques that may work for pyriproxyfen dissemination. Future studies evaluating the dissemination of pyriproxyfen formulated as a gel, or similar carriers that can bind to a female mosquito during oviposition should be conducted.

Technical Abstract: The Asian tiger mosquito, Aedes albopictus (Skuse), ranks among the most significant vectors of dengue fever and chikungunya virus. With no specific medications or vaccines available, vector control is the only way to combat these diseases. Autodissemination of the insect growth regulator NyGuard® (pyriproxyfen) from a point source treatment was evaluated in field settings in Northeast Florida. The objective of this study was to investigate the possibility of pyriproxyfen dissemination from a treatment site to non-treated oviposition sites via the skip oviposition behavior of Ae. albopictus. A spray application was made to a tire pile using a Stihl® SR 420 backpack sprayer. Autodissemination oviposition vases containing oak infusion water were positioned in groups of five at 25 to 400m in four transects surrounding the tire pile. Two sets of 5 control vases containing oak infusion water were placed 1500 m from the tire pile and oak infusion water samples were collected directly from the tire pile. Fifty milliliter samples were extracted from each vase weekly and preserved for pyriproxyfen residue analysis. All vases were analyzed at week 0 (4 hrs post-treatment), 1, 2, 4 and 6. Overall, there were no differences between the control and autodissemination vases. The tire pile samples had significantly more mortality (p< 0.0001) out to 4 weeks when compared to autodissemination and control vases.