Improved Molecular Detection ofAngiostrongylus cantonensisin Mollusks and Other Environmental Samples with a Species-Specific Internal Transcribed Spacer 1-Based TaqMan Assay

Abstract

Angiostrongylus cantonensis is the most common cause of human eosinophilic meningitis. Humans become infected by ingesting food items contaminated with third-stage larvae that develop in mollusks. We report the development of a real-time PCR assay for the species-specific identification of A. cantonensis in mollusk tissue.

Hurdles in the evolutionary epidemiology of Angiostrongylus cantonensis: Pseudogenes, incongruence between taxonomy and DNA sequence variants, and cryptic lineages

“…Thus, experiments are needed to determine trait distributions within clades (or subclades) and where possible, definitively link morphological traits to the molecular‐based phylogenetic lineages. In addition, current molecular diagnostic tools rely on rDNA (Qvarnstrom et al., 2010), which does not have as much variation as mtDNA. The geographic affiliations of subclades given in Table 3 suggest global distributions could be limited to just some subclades.…”

“…Indeed, the use of DNA data only came about in the 2000s. For example, ribosomal DNA sequences were used to assess metastrongylid nematode relationships (Carreno & Nadler, 2003) or to help survey larvae from mollusk intermediate hosts (Fontanilla & Wade, 2008; Qvarnstrom, Sullivan, Bishop, Hollingsworth, & da Silva, 2007; Qvarnstrom et al., 2010), and ~360‐bp region of the cytochrome c oxidase 1 ( CO 1) gene was used to assess relationships to other species of Angiostrongylus (Eamsobhana et al., 2010). To date, molecular systematic/phylogeographic studies on A. cantonensis have mainly used two mitochondrial (mtDNA) markers, CO 1 and cytochrome b ( CYTB ), where the focus has largely been descriptive in terms of reporting local patterns of haplotype variants (Aghazadeh et al., 2015; Dalton, Fenton, Cleveland, Elsmo, & Yabsley, 2017; Dusitsittipon, Criscione, Morand, Komalamisra, & Thaenkham, 2017; Dusitsittipon, Thaenkham, Watthanakulpanich, Adisakwattana, & Komalamisra, 2015; Eamsobhana, Song, et al., 2017; Eamsobhana, Yong, et al., 2017; Lv et al., 2012; Monte et al., 2012; Moreira et al., 2013; Nakaya et al., 2013; Okano et al., 2014; Rodpai et al., 2016; Simoes et al., 2011; Tokiwa et al., 2012, 2013; Vitta et al., 2016; Yong, Eamsobhana, Song, Prasartvit, & Lim, 2015; Yong, Song, Eamsobhana, Goh, & Lim, 2015; Yong, Song, Eamsobhana, & Lim, 2016).…”

Eosinophilic meningoencephalomyelitis in an orangutan (Pongo pygmaeus) caused byAngiostrongylus cantonensis

“…Real-time polymerase chain reaction (PCR) analysis (Qvarnstrom et al 2010) of the paraffin-embedded brain tissue performed by the Centers for Disease Control and Prevention (CDC) confirmed infection with A. cantonensis. Snails were subsequently collected from Florida and South Carolina locations.…”

First report of Angiostrongylus cantonensis in Porto Alegre, State of Rio Grande do Sul, Southern Brazil

“…According to Wang et al 1 , more than 2,820 cases have been reported in approximately 30 countries, mostly in Asia and the Pacifi c Islands. A. cantonensis infection has been increasingly detected in travelers returning from endemic areas 2 and is now considered to be a growing food safety concern 3 . Laboratory isolation and identifi cation of this parasite were reported for the fi rst time in Brazil in the State of Espírito Santo after eosinophilic meningitis was diagnosed in two patients 4 , followed by its detection in two patients in Pernambuco 5 .…”