A Biodegradable Lethal Ovitrap for Control of Container-Breeding Aedes

Abstract

Lethal ovitraps (LO) have been successfully deployed in dengue control operations in north Queensland, Australia since 2004. However, the current plastic-bucket LO must be retrieved before the pesticide-treated strip degrades and the trap begins producing mosquitoes. The logistics involved with trap retrieval are considerable and include recording trap location and retrieval date onto a database, locating and retrieving each trap, and examining lethal ovitraps for eggs. Collectively, these necessary activities greatly reduce the efficiency of dengue control. In response, we have developed a biodegradable lethal ovitrap (BLO) that does not need to be retrieved for the control of container-breeding Aedes, particularly Aedes aegypti. The BLOs were made by injection molding with the use of 2 proprietary blends of thermoplastic starch (TPS) polymer based on plasticised amylose maize polymers. In field trials, Ae. aegypti readily oviposited in BLOs, with those dyed black with the use of carbon black preferred. Water loss was higher in BLOs than in standard plastic LO because of weeping from the walls, although none of the BLOs failed in the 5 wk of the trial. The occurrence and rate of Ae. aegypti oviposition in both BLOs and the LO was comparable. In an accelerated standard composting trial (ISO16929:2002E), both BLOs fragmented within 4 wk, and no BLO particles were visible after 12 wk. Large numbers of BLOs could be deployed in a "set it and forget it" strategy to control Ae. aegypti and to stop dengue transmission, and could be used in a community participation program to maximize coverage.

The Effects of Sustained Release Metofluthrin on the Biting, Movement, and Mortality of Aedes aegypti in a Domestic Setting

“…Nevertheless, field trials using metofluthrin over large contiguous areas are warranted. Registered metofluthrin emanators, in concert with biodegradable lethal ovitraps, 21 could be provided to the public as part of a "do it yourself" community participation dengue control strategy. If metofluthrin emanators were commercially available, media campaigns and websites (e.g., http://www.health.qld.gov.au/ dengue/default.asp ) encouraging their use during an outbreak could be effective.…”

Development and evaluation of a novel contamination device that targets multiple life-stages of Aedes aegypti

“…Novel ovitraps were therefore designed to also target the adult mosquito. These traps include designs such as the ‘sticky’ trap [7,16,17] or ‘double-sticky’ trap [8] in which gravid mosquitoes are captured using glue, or lethal ovitraps [18-20] in which mosquitoes are exposed to insecticides. A major disadvantage of these lethal ovitraps is the fact that insecticides deployed in such traps have shown reduced efficacy due to widespread insecticide resistance in Aedes populations [21].…”

Aedes aegypti (Diptera: Culicidae): evaluation of natural long-lasting materials containing pyriproxyfen to improve control strategies

“…Perich et al (2003) found reduction of A. aegypti in Brazil, but studies performed in Thailand gave mixed results (Sithiprasasna et al 2003). Different trials in Australia showed an acceptable performance of these LOs but created several additional operational problems which could be solved by using biodegradable ovitraps (Ritchie et al 2008).…”

“…Different devices have been studied and are now commercialized. In some of them, the rough egg-laying wooden paddle was replaced by a velour paper strip treated with an insecticide like deltamethrin or bifenthrin while others added a sticky surface Williams et al 2007;Ritchie et al 2008Ritchie et al , 2009Rapley et al 2009;Chadee and Ritchie 2010). The newest ones make them more attractive to oviposit (Attractant-Bait Lethal Ovitrap ALOT) in which the ovitrap is filled with water laced with attractants and the container is lined with a fabric impregnated with an insecticide to kill the adults when they land to oviposit their eggs (Wesson et al 2012).…”