RapidSalmonelladetection in experimentally inoculated equine faecal and veterinary hospital environmental samples using commercially available lateral flow immunoassays

Autor: Paul S. Morley, Brandy A. Burgess, D.C. Van Metre, Noelle R. Noyes, Doreene R. Hyatt, Denise Bolte
Rok vydání: 2014
Předmět:
Zdroj: Equine Veterinary Journal. 47:119-122
ISSN: 0425-1644
DOI: 10.1111/evj.12234
Popis: Summary Reasons for performing study Salmonella enterica is the most commonly reported cause of outbreaks of nosocomial infections in large animal veterinary teaching hospitals and the closure of equine hospitals. Rapid detection may facilitate effective control practices in equine populations. Shipping and laboratory testing typically require ≥48 h to obtain results. Lateral flow immunoassays developed for use in food-safety microbiology provide an alternative that has not been evaluated for use with faeces or environmental samples. Objectives We aimed to identify enrichment methods that would allow commercially available rapid Salmonella detection systems (lateral flow immunoassays) to be used in clinical practice with equine faecal and environmental samples, providing test results in 18–24 h. Study design In vitro experiment. Methods Equine faecal and environmental samples were inoculated with known quantities of S. enterica serotype Typhimurium and cultured using 2 different enrichment techniques for faeces and 4 enrichment techniques for environmental samples. Samples were tested blindly using 2 different lateral flow immunoassays and plated on agar media for confirmatory testing. Results In general, commercial lateral flow immunoassays resulted in fewer false-negative test results with enrichment of 1 g faecal samples in tetrathionate for 18 h, while all environmental sample enrichment techniques resulted in similar detection rates. The limit of detection from spiked samples, ∼4 colony-forming units/g, was similar for all methods evaluated. Conclusions The lateral flow immunoassays evaluated could reliably detect S. enterica within 18 h, indicating that they may be useful for rapid point-of-care testing in equine practice applications. Additional evaluation is needed using samples from naturally infected cases and the environment to gain an accurate estimate of test sensitivity and specificity and to substantiate further the true value of these tests in clinical practice.
Databáze: OpenAIRE