A new multiplex real-time pcr assay to improve the diagnosis of shellfish regulated parasites of the genus marteilia and bonamia

Type Article
Date 2020-10
Language English
Author(s) Canier Lydie1, Dubreuil ChristineORCID1, Noyer Mathilde1, Serpin Delphine1, Chollet Bruno1, Garcia Celine1, Arzul IsabelleORCID1
Affiliation(s) 1 : Ifremer, RBE-SG2M-LGPMM, Station de La Tremblade, Avenue de Mus de Loup, F-17390 La Tremblade, France
Source Preventive Veterinary Medicine (0167-5877) (Elsevier BV), 2020-10 , Vol. 183 , P. 105126 (8p.)
DOI 10.1016/j.prevetmed.2020.105126
Keyword(s) multiplex real-time PCR, Bonamia spp., Marteilia refringens, flat oysters, diagnostic accuracy study, Inter laboratory comparison
Abstract

Aquaculture including shellfish production is an important food resource worldwide which is particularly vulnerable to infectious diseases. Marteilia refringens, Bonamia ostreae and Bonamia exitiosa are regulated protozoan parasites infecting flat oysters Ostrea edulis that are endemic in Europe. Although some PCR assays have been already developed for their detection, a formal validation to assess the performances of those tools is often lacking. In order to facilitate the diagnosis of flat oyster regulated diseases, we have developed and evaluated a new multiplex Taqman® PCR allowing the detection of both M. refringens and Bonamia sp. parasites in one step.

First part of this work consisted in assessing analytical sensitivity and specificity of the new PCR assay. Then, diagnostic performances were assessed by testing a panel of field samples with the new real-time PCR and currently recommended conventional PCR methods for the detection of M. refringens and Bonamia sp. Samples were collected from the main flat oyster production sites in France (N = 386 for M. refringens and N = 349 for B. ostreae). In the absence of gold standard, diagnostic sensitivity and specificity of the new PCR were estimated through Bayesian latent class analysis (DSe 87,2% and DSp 98,4% for the detection M. refringens, DSe 77,5% and DSp 98,4% for the detection of Bonamia sp.). Those results suggest equivalent performances for the detection of Bonamia sp. and an improved sensitivity for the detection of M. refringens compared to commonly used conventional protocols. Finally, the new PCR was evaluated in the context of an inter-laboratory comparison study including 17 European laboratories. Results revealed a very good reproducibility with a global accordance (intra-laboratory precision) >96% and a global concordance (inter-laboratory precision) >93% for both targets, demonstrating that this new tool is easily transferable to different laboratory settings.

This is the first assay designed to detect both Marteilia refringens and Bonamia sp. in a single step and it should allow reducing the number of analysis to monitor both diseases, and where relevant to demonstrate freedom from infection.

Full Text
File Pages Size Access
Author's final draft 36 877 KB Open access
257 KB Access on demand
8 401 KB Access on demand
Top of the page

How to cite 

Canier Lydie, Dubreuil Christine, Noyer Mathilde, Serpin Delphine, Chollet Bruno, Garcia Celine, Arzul Isabelle (2020). A new multiplex real-time pcr assay to improve the diagnosis of shellfish regulated parasites of the genus marteilia and bonamia. Preventive Veterinary Medicine, 183, 105126 (8p.). Publisher's official version : https://doi.org/10.1016/j.prevetmed.2020.105126 , Open Access version : https://archimer.ifremer.fr/doc/00643/75523/