Ultrasonic Technology Applied against Mosquito Larvae

Abstract

The effective management of mosquito vectors is a timely challenge for medical and veterinary entomology. In this study, we evaluated the acoustic Larvasonic device to control young instars of the mosquito Aedes aegypti in diverse freshwater environments. Under laboratory conditions, we investigated the effect of exposure time and distance from the transducer on the mortality of larvae and pupae of Ae. aegypti. Furthermore, we evaluated the effectiveness of the ultrasound window of the electromagnetic spectrum under different field conditions. Results showed that first and second instar larvae were more sensitive to the frequency range of 18–30 kHz of the Larvasonic device. Ultrasonic waves applied for 180 s at a frequency from 18 to 30 kHz caused 100% larval mortality at a distance of 60 cm from the transducer. No mortality was observed in the non-target copepod Megacyclops formosanus. The exposure to the soundwaves produced by the acoustic larvicidal device over different distances effectively damaged Ae. aegypti through destruction of the larval dorsal tracheal trunk, thorax and abdomen. Overall, results indicated that the Larvasonic device tested can provide an alternative tool to reduce young instar populations of Ae. aegypti, without any effects on non-target aquatic invertebrates like copepods. It turned out to be a useful device for mosquito biocontrol. This technology has a relevant potential to fight the spread of mosquito-borne diseases.

Vector Control Strategies

“…Furthermore, the lowest resonating energies affect other structures, inhibiting the emergence of larvae. In conclusion, mortality is the result of both effects [76,77]. The lowest frequencies (20-50 kHz) are known to be more effective as larvicidal than higher frequencies (>100 kHz) [77].…”

“…In conclusion, mortality is the result of both effects [76,77]. The lowest frequencies (20-50 kHz) are known to be more effective as larvicidal than higher frequencies (>100 kHz) [77]. However, when other aquatic insects, such as Diptera, Hemiptera, and Coleoptera that have open tracheal systems, are exposed to the acoustic beam for a prolonged period they may be adversely affected [78].…”

“…aegypti and Cu. quinquefasciatus (100%), both laboratory and field conditions and did not affect larvae predators, such as Methanofollis formosanus, Poecilia reticulata (Guppy fish), Xiphophorus helleri (Swordtail fish), Micronecta grisea (small water-boatmen) and Indoplanorbis exustus (freshwater snails) [76,77,79]. The promising nature of this system resides in the low risk of resistance development in target mosquito populations and this equipment can be used as a complement to the chemical or biological larvicides that have been used in control programmes under specific operational conditions [78].…”

Biological and Chemical Control of Mosquito Population by Optimal Control Approach

“…A shallow basin we consider here has the volume of about 100 liters, and a maximal larval density is 8-10 individuals per liter [34] what gives us the carrying capacity K q = 1 (measured in thousands of individuals). We also assume the following stylized values related to the predacious species…”

The lethal effects of high-frequency ultrasound waves in Pediculus humanus capitis (Anoplura: Pediculidae) nymphs and adults

“…Highfrequency ultrasound waves are reported to be one of the candidate mechanical control agents to prevent infestations caused by ectoparasitic arthropods in humans, and domestic animals. Ultrasonic sounds (> 20 kHz) are employed in daily life, and technology, are not audible to humans but can harm some arthropod pests (Kalimuthu et al 2020).…”