Larvicidal Efficacy of Ozone and Ultrasound on Angiostrongylus cantonensis (Rat Lungworm) Third-Stage Larvae

Abstract

The parasitic nematode Angiostrongylus cantonensis (rat lungworm) is the leading cause of human eosinophilic meningitis worldwide. Most human infections occur through the accidental consumption of A. cantonensis hidden within produce as infectious third-stage larvae (L3), yet little research has been published addressing possible methods to mitigate this means of transmission. Here, we describe our tests of ozone gas—an oxidizing agent—and ultrasound, both used for disinfection of food and municipal water supplies and in industrial cleaning. We found that exposure to ozone, produced using two different commercially available ozone generators over varying durations of time and concentrations, was capable of achieving 100% larval mortality. In addition, we evaluated the impact of different sound frequencies on A. cantonensis L3 survival using two different commercially available ultrasonic cleaners, and found that 60 s of 40 kHz produced 46% mortality within 2 h. The combined use of ultrasound and ozone gas simultaneously resulted in a minimum of 89% normalized mean percent mortality within 2 h of treatment. Our study suggests that both ozone and ultrasound show high larvicidal efficacy, both independently and together, and thus show promise as methods for reducing the risk of rat lungworm infection via accidental consumption.

Identification and coregulation pattern analysis of long noncoding RNAs in the mouse brain after Angiostrongylus cantonensis infection

“…The third-stage larvae of A. cantonensis are its infective form [ 10 ], and its life cycle is completed mainly in rats and snails; gastropods, such as slugs and snails, are its intermediate hosts and mammals, such as rats, are its final hosts [ 11 ]. More than 20 vertebrate species, including humans, may serve as accidental hosts, while amphibians and fish may serve as transfer hosts [ 12 – 14 ]. A. cantonensis may develop into adult nematodes in rats only; mice and humans are nonpermissive hosts [ 15 ].…”