Inactivation of foot-and-mouth disease virus in epithelium samples for safe transport and processing in low-containment laboratories

https://doi.org/10.1016/j.jviromet.2019.113770Get rights and content

Abstract

During a foot-and-mouth disease (FMD) outbreak, transport and testing of potentially infectious samples, including epithelium from suspect lesions, presents a biosafety risk, particularly in FMD-free countries. Therefore, treatment to inactivate virus prior to transport is important. Tongue epithelium from cattle infected with FMD virus (FMDV) serotype O (O ALG/3/2014 – Lineage O/ME-SA/Ind-2001d) or A (A IRN/22/2015 – Lineage A/ASIA/G-VII) was incubated in RNAlater, RNA Shield or phosphate-buffered saline (pH 7.4) at room temperature for 2, 6, 24 or 48 h. After incubation, tissues were homogenised and tested by virus titration. Viral RNA in the homogenate was quantified by RT-qPCR, used for sequencing, and transfected into LFBKαVβ6 cells to recover infectious virus.

RNAlater reduced A IRN/22/2015 titres by 4 log10 after 24 h, and completely after 48 h incubation. While O ALG/3/2014 was detected by VI after 2, 6 and 24 h, titration yielded no infectious virus, likely as a result of freeze-thawing. RNA Shield was cytotoxic at high concentrations but was effective at inactivating both strains after 24 h. Regardless of reagent or inactivation period, RT-qPCR, VP1 sequencing, and transfection of RNA to recover infectious virus were possible. RNA Shield appears a better choice for FMDV inactivation in tissues, however 24 h incubation is recommended.

Section snippets

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

This project is supported by Meat & Livestock Australia (MLA), through funding from the Australian Government Department of Agriculture and Water Resources as part of its Rural R&D for Profit program, and by producer levies from Australian FMD-susceptible livestock (cattle, sheep, goats and pigs) industries and Charles Sturt University (CSU), leveraging significant in-kind support from the research partners. The research partners for this project are the Commonwealth Science and Industrial

References (17)

There are more references available in the full text version of this article.

Cited by (7)

  • Chemical inactivation of foot-and-mouth disease virus in bovine tongue epithelium for safe transport and downstream processing

    2022, Journal of Virological Methods
    Citation Excerpt :

    Apart from an apparent reduction in viral RNA in O/ALG/3/2014 samples treated with PAXgene Tissue System Stabiliser at all time points compared to all other samples, there was no drastic effect on RT-qPCR RNA detection following incubation with the different buffers, up to at least 48 h (Fig. 2). Sequencing of the VP1 capsid protein coding region (1D) of FMDV is widely used for determination of serotype, lineage and strain which aids in outbreak characterisation and vaccine strain selection (Dill and Eschbaumer, 2019; Horsington et al., 2020). RNA specimens extracted from the 24-h incubation samples (n = 64) were tested as follows.

View all citing articles on Scopus
View full text