title: Detection of Influenza A virus in porcine oral fluid samples.
abstract: Porcine oral fluids have been used for the detection of Porcine reproductive and respiratory syndrome virus and Porcine circovirus-2. The objective of the present study was to determine whether Influenza A virus (FLUAV) is present in porcine oral fluids at detectable levels and to validate a standard FLUAV molecular diagnostic test for porcine oral fluids. Pen-based oral fluid samples were collected on 3, 4, 5, and 6 days postinfection (DPI) from 4 groups of 6 pigs each that were inoculated intratracheally with A/Swine/Iowa/00239/2004 H1N1 and from 2 untreated or mock-inoculated groups of 6 pigs each that served as negative controls. Individual nasal swabs were also collected from these 36 pigs on 3 and 7 DPI. All oral fluid samples were examined for the presence of FLUAV by matrix gene real-time reverse transcription polymerase chain reaction (real-time RT-PCR) and virus isolation. Nasal swabs were tested initially by virus isolation followed by retest of negative samples with real-time RT-PCR. No oral fluid sample from virus-inoculated pigs was positive by virus isolation, but 15 of 16 positive (94%) oral fluids were positive by real-time RT-PCR. In contrast, virus was isolated from 32 of 48 (67%) nasal swabs collected from virus-inoculated pigs. In addition, 382 of 910 porcine oral fluids collected from pigs in the field between August 1, 2009, and January 31, 2010, were positive by real-time RT-PCR. The results of the present study indicate that pen-based oral fluids provide an easy, effective, and safe collection method for the detection of FLUAV with rapid testing methods such as real-time RT-PCR.
authors.affiliation: University of Minnesota, College of Veterinary Medicine, 1365 Gortner Avenue, St Paul, MN 55108, USA. detm0002@umn.edu
authors.forename: Susan E
authors.initials: SE
authors.lastname: Detmer
authors.forename: Devi P
authors.initials: DP
authors.lastname: Patnayak
authors.forename: Yin
authors.initials: Y
authors.lastname: Jiang
authors.forename: Marie R
authors.initials: MR
authors.lastname: Gramer
authors.forename: Sagar M
authors.initials: SM
authors.lastname: Goyal
mesh_terms: D000818:Animals; D016009:Chi-Square Distribution; D007150:Immunohistochemistry; D053118:Influenza A Virus, H1N1 Subtype / Q000235:genetics / Q000302:isolation & purification*; D009976:Orthomyxoviridae Infections / Q000175:diagnosis / Q000662:veterinary* / Q000821:virology; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics; D011897:Random Allocation; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary*; D012463:Saliva / Q000821:virology*; D013552:Swine; D013553:Swine Diseases / Q000175:diagnosis / Q000821:virology*
chemical_list: D012367:RNA, Viral