Oviposition substrate in Asian tiger mosquito surveillance: Do the sizes matter?

Abstract

Ovitraps are regarded as a reliable system to monitor Aedes albopictus dynamics. However, the dimensions of the oviposition substrate are not standardized, and no studies have investigated which should be the most effective sizes. In this study, the effect of paddle sizes in tiger mosquito egg collection was evaluated. Egg count and density on the wide surfaces and margins of different-sized oviposition substrates have been evaluated in two studies (A and B). In study A, a total of 29,995 Ae. albopictus eggs was counted in 250 classic oviposition substrates. Eggs were found on both wide surfaces (53.1%) and margins (46.9%). Egg density was significantly larger in margins compared to wide surfaces. Overall in study B, 983 Ae. albopictus eggs were collected. According to paddle sizes, 51.8% of eggs were on large and 48.2% on small paddles. Mean egg density of wide surfaces was significantly larger in small paddles (0.25 eggs/cm 2 ) compared to large paddles (0.06 eggs/cm 2 ). Results indicate that wider oviposition substrates do not mean larger number of Ae. albopictus eggs. Indeed, on paddles four times thinner than others, the number of eggs counted was not statistically different. These findings suggest that small paddles may be routinely employed in ovitraps, thus allowing savings of materials and money. Journal of Vector Ecology 40 (2): 256-261. 2015.

Proof of Concept of Biopolymer Based Hydrogels as Biomimetic Oviposition Substrate to Develop Tiger Mosquitoes (Aedes albopictus) Cost-Effective Lure and Kill Ovitraps

“…It was observed that the ovipositing females preferred physical hydrogels to control, whereas the crosslinked hydrogels showed a repellent effect (almost no oviposition), probably due to smooth surfaces and Cl residuals from the crosslinking process, which are already known as deterrents for Aedes albopictus oviposition [ 60 , 78 , 79 , 80 ]. In particular, it was found that a 2-Hydroxyethylcellulose-based hydrogel formulation (HEC16) containing 16 wt% of polymer can attract ovipositing tiger mosquitoes more than control.…”

Rapid Surveillance for Vector Presence (RSVP): Development of a novel system for detecting Aedes aegypti and Aedes albopictus

“…Molecular analyses mitigates the risk of human error in detecting a small number of specimens of an invasive species that are obscured by many 1,000s of larvae from endemic species [64]. Hatching eggs to 1 st instar larvae prior to RT-PCR analysis removes requirements for a specific ovitrap format (design, size, material), ovistrip size [65] or substrate (e.g., cloth, paper, germination paper, wood). Shipment of large numbers of egg samples by postal service is also potentially more logistically viable than couriering water samples for newly developed environmental DNA analysis [66].…”