Efficacy of chemical disinfectants for the containment of the salamander chytrid fungus Batrachochytrium salamandrivorans.

Pascale Van Rooij,An Martel,Frank Pasmans,Yanaika Coen,Jake Kerby

doi:10.1371/journal.pone.0186269

Abstract

The recently emerged chytrid fungus Batrachochytrium salamandrivorans (Bsal) causes European salamander declines. Proper hygiene protocols including disinfection procedures are crucial to prevent disease transmission. Here, the efficacy of chemical disinfectants in killing Bsal was evaluated. At all tested conditions, Biocidal®, Chloramine-T®, Dettol medical®, Disolol®, ethanol, F10®, Hibiscrub®, potassium permanganate, Safe4®, sodium hypochlorite, and Virkon S®, were effective at killing Bsal. Concentrations of 5% sodium chloride or lower, 0.01% peracetic acid and 0.001–1% copper sulphate were inactive against Bsal. None of the conditions tested for hydrogen peroxide affected Bsal viability, while it did kill Batrachochytrium dendrobatidis (Bd). For Bsal, enzymatic breakdown of hydrogen peroxide by catalases and specific morphological features (clustering of sporangia, development of new sporangia within the original sporangium), were identified as fungal factors altering susceptibility to several of the disinfectants tested. Based on the in vitro results we recommend 1% Virkon S®, 4% sodium hypochlorite and 70% ethanol for disinfecting equipment in the field, lab or captive setting, with a minimal contact time of 5 minutes for 1% Virkon S® and 1 minute for the latter disinfectants. These conditions not only efficiently target Bsal, but also Bd and Ranavirus.

Highlights

Skin infection caused by the chytrid fungus Batrachochytrium salamandrivorans (Bsal) is an important threat to native European salamander species [1,2]
All concentrations tested for Biocidal1, Safe41, F101, 70% EtOH, Disolol1and Hibiscrub1 and bleach containing 4% sodium hypochlorite (NaOCl) displayed a rapid action and killed Batrachochytrium dendrobatidis (Bd) and Bsal within 30 seconds
Our results show that a number of chemical disinfectants cause 100% mortality of Bsal in vitro within a relatively short time

Summary

Introduction

Skin infection caused by the chytrid fungus Batrachochytrium salamandrivorans (Bsal) is an important threat to native European salamander species [1,2]. Since its emergence in 2010, Bsal has been detected in the Netherlands, Belgium and Germany and will most likely establish permanently within Western Europe [3]. The number of captive collections coping with Bsal outbreaks is increasing [4,5,6]. In this context, taking measures to prevent or minimize human-mediated spread of Bsal to naïve populations or regions is of paramount importance. The development of proper hygiene protocols, for use in the field, captive collections or laboratories is crucial.

Methods

Results

Conclusion