Poor biosecurity could lead to disease outbreaks in animal populations.

Matthew J Gray,E Davis Carter,Jennifer A Spatz,Christian M Yarber,Debra L Miller,Rebecca P Wilkes,Jake Kerby

doi:10.1371/journal.pone.0193243

Matthew J Gray, E Davis Carter + Show 5 more

Open Access

https://doi.org/10.1371/journal.pone.0193243

Copy DOI

Abstract

Human-mediated disease outbreaks due to poor biosecurity practices when processing animals in wild populations have been suspected. We tested whether not changing nitrile gloves between processing wood frog (Lithobates sylvaticus) tadpoles and co-housing individuals increased pathogen transmission and subsequent diseased-induced mortality caused by the emerging pathogen, ranavirus. We found that not changing gloves between processing infected and uninfected tadpoles resulted in transmission of ranavirus and increased the risk of mortality of uninfected tadpoles by 30X. Co-housing tadpoles for only 15 minutes with 10% of individuals infected resulted in ranavirus transmission and 50% mortality of uninfected tadpoles. More extreme mortality was observed when the co-housing infection prevalence was >10%. Our results illustrate that human-induced disease outbreaks due to poor biosecurity practices are possible in wild animal populations.

Highlights

Humans can play a role in the emergence of infectious diseases in animal populations
We considered a sample infected if the qPCR cycle threshold (CT) value was less than 32 based on standardized optimization with known quantities of ranavirus
Our study demonstrates that poor biosecurity practices can increase pathogen transmission and disease-related mortality in wild amphibians that are processed as part of routine epidemiological and biological studies

Summary

Introduction

Humans can play a role in the emergence of infectious diseases in animal populations. Examples of pathogen pollution include the emergence of Pseudogymnoascus destructans in North American bat populations and the emergence of Batrachochytrium salamandrivorans in European salamander populations [3, 4]. Another way that humans can alter disease processes in animal populations is by facilitating pathogen transmission. Some pathogens can be shed through the skin [10, 11], handling different individuals without changing gloves could facilitate transmission. We tested the possibility of human-mediated pathogen transmission if gloves were not changed between handling infected and uninfected amphibians, and if infected and uninfected individuals were co-housed.

Methods

Results

Conclusion