Journal Article

Assessing the value of PCR assays in oral fluid samples for detecting African swine fever, classical swine fever, and foot-and-mouth disease in U.S. swine

Beemer, Oriana, Remmenga, Marta, Hsi, David, Antognoli, Maria Celia, Johnson, Kamina, Gustafson, Lori

2019

Overview

Oral fluid sampling and testing offers a convenient, unobtrusive mechanism for evaluating the health status of swine, especially grower and finisher swine. This assessment evaluates the potential testing of oral fluid samples with real-time reverse-transcriptase polymerase chain reaction (rRT-PCR) to detect African swine fever, classical swine fever, or foot-and-mouth disease for surveillance during a disease outbreak and early detection in a disease-free setting. We used a series of logical arguments, informed assumptions, and a range of parameter values from literature and industry practices to examine the cost and value of information provided by oral fluid sampling and rRT-PCR testing for the swine foreign animal disease surveillance objectives outlined above. Based on the evaluation, oral fluid testing demonstrated value for both settings evaluated. The greatest value was in an outbreak scenario, where using oral fluids would minimize disruption of animal and farm activities, reduce sample sizes by 23%-40%, and decrease resource requirements relative to current individual animal sampling plans. For an early detection system, sampling every 3 days met the designed prevalence detection threshold with 0.95 probability, but was quite costly. Implementation of oral fluid testing for African swine fever, classical swine fever, or foot-and-mouth disease surveillance is not yet possible due to several limitations and information gaps. The gaps include validation of PCR diagnostic protocols and kits for African swine fever, classical swine fever, or foot-and-mouth disease on swine oral fluid samples; minimal information on test performance in a field setting; detection windows with low virulence strains of some foreign animal disease viruses; and the need for confirmatory testing protocol development.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: African swine fever / African Swine Fever - diagnosis / Animal diseases / Animal health / Animals / Asfarviridae - isolation & purification / Biology and Life Sciences / Classical Swine Fever - diagnosis / Classical Swine Fever Virus - isolation & purification / Computer viruses / detection limit / Diagnosis / Diagnostic systems / Disease control / disease surveillance / Disruption / Epidemiology / farms / Fever / Foot & mouth disease / Foot and mouth disease / Foot-and-Mouth Disease - diagnosis / Foot-and-Mouth Disease Virus - isolation & purification / Health aspects / health status / hog cholera / Hogs / industry / Laboratories / Livestock / Medicine and Health Sciences / monitoring / Mouth Mucosa - virology / Oral fluids / Outbreaks / Polymerase chain reaction / Prevalence / Probability / Real-Time Polymerase Chain Reaction - economics / Real-Time Polymerase Chain Reaction - veterinary / Reproducibility of Results / reverse transcriptase polymerase chain reaction / Reverse Transcriptase Polymerase Chain Reaction - economics / Reverse Transcriptase Polymerase Chain Reaction - veterinary / Risk factors / RNA, Viral - analysis / Saliva - virology / Sampling / Sensitivity and Specificity / Social Sciences / Surveillance / Swine / Test procedures / transboundary animal diseases / United States / Virulence / Viruses