PEDV monitoring using oral fluid, feces and surface swab samples after the PED outbreak

Abstract

A total of 220 pooled samples from 3 collection times were conducted. Eighty pooled samples from the first collection at 1 month after PED outbreak (1MAO) included 10 pooled oral fluid samples, 30 pooled fecal samples and 40 pooled surface swab samples. Eighty-five pooled samples from the second collection at 2MAO included 10 pooled oral fluid samples, 30 pooled fecal samples and 45 pooled surface swab samples. Fifty-five pooled samples from the third collection at 8MAO included 5 pooled oral fluid samples, 15 pooled fecal samples and 35 pooled surface swab samples. All samples collected from the PED-affected swine farm in Chonburi province, Thailand between July 2017 to February 2018. The objective of this study was to evaluate the existence of PEDV residues in pigs and fomites in the affected swine farm after the PED outbreak and gut feedback protocol was implemented. Oral fluid, fecal and surface swab samples were collected to monitor the existence of the residue virus after the outbreak when practicing gut feedback protocol. The results showed that all pooled samples were positive to PEDV for 20 pooled samples (20/220, 9%). The samples at first collection (1MAO) were positive to PEDV (2/80, 2.5%) from a primiparous sow pen after 3 weeks farrowing and a multiparous sow pen after 3 weeks farrowing. The highest prevalence was found in the second sample collection (2MAO) and positive to PEDV (18/85, 21.17%) by 2 positive feces samples from multiparous gestated sows and multiparous sow after 1 week farrowing and 16 positive samples of surface swab samples from 1 positive sample from empty farrowed barn, 5 positive samples from primiparous sow pen after 1 week farrowing, 5 positive sample from multiparous sow pen after 1 week farrowing, 3 positive sample from primiparous sow pen after 3 week farrowing, 2 positive sample from multiparous sow pen after 3 week farrowing and no positive samples were found at the third sample collection (8 MAO). There have no any positive oral fluid samples from all samples. These findings demonstrated that fecal sample and surface swab sample could be used for PEDV detection after the outbreak up to 2 months when using gut feedback protocol. Viral eradication on the surface areas of the affected farm and PEDV monitoring from the fecal samples could be the effective tools for the prevention and control strategy.