Evaluation of two real-time polymerase chain reaction assays for Porcine epidemic diarrhea virus (PEDV) to assess PEDV transmission in growing pigs
| Autor: | Steven G. Kellner, Kelly M. Lager, Kimberly Crawford, Susan L. Brockmeier, Laura C. Miller |
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| Rok vydání: | 2015 |
| Předmět: |
0301 basic medicine
Swine Coefficient of variation Biology Real-Time Polymerase Chain Reaction Feces 03 medical and health sciences Disease Transmission Infectious Animals Swine Diseases General Veterinary Transmission (medicine) Porcine epidemic diarrhea virus Transmission potential Reverse Transcription biology.organism_classification Virology United States Reverse transcriptase Reverse transcription polymerase chain reaction 030104 developmental biology Real-time polymerase chain reaction Animals Newborn Coronavirus Infections |
| Zdroj: | Journal of Veterinary Diagnostic Investigation. 28:20-29 |
| ISSN: | 1943-4936 1040-6387 |
| Popis: | In April 2013, a Porcine epidemic diarrhea virus (PEDV) epidemic began in the United States. As part of the response, real-time reverse transcription polymerase chain reaction (RT-PCR) assays to detect PEDV were developed by several veterinary diagnostic laboratories. Our study evaluated RT-PCR PEDV assays that detect the N gene ( gN) and S gene ( gS) for their ability to detect PEDV infection and the transmission potential of pigs experimentally exposed to PEDV. Detection limits and quantification cycle (Cq) values of real-time RT-PCR were assayed for PEDV samples and positive controls for both gN and gS. The limit of detection for the gN assay was 10−6 (mean Cq: 39.82 ± 0.30) and 10−5 (mean Cq: 39.39 ± 0.72) for the gS assay with PEDV strain USA/Colorado/2013. Following recommended guidelines, rectal swabs ( n = 1,064) were tested; 354 samples were positive by gN assay and 349 samples were positive by gS assay (Cq ≤ 34.99), 710 samples were negative by gN assay and 715 were negative by gS assay (Cq > 34.99) of which 355 and 344 were “undetermined” (i.e., undetected within a threshold of 40 RT-PCR cycles, by gN and gS assays, respectively). The coefficient of variation (intra-assay variation) ranged from 0.00% to 2.65% and interassay variation had an average of 2.75%. PEDV could be detected in rectal swabs from all pigs for ~2 weeks postinfection at which time the prevalence began to decrease until all pigs were RT-PCR negative by 5 weeks postinfection. Our study demonstrated that RT-PCR assays functioned well to detect PEDV and that the gN assay was slightly better. |
| Databáze: | OpenAIRE |
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