Development and validation of indirect ELISA for antibody detection against different protein antigens of porcine epidemic diarrhea virus in the colostrum and milk of sows.

The objectives of this study are to develop and optimize indirect ELISA based on three coating antigens of porcine epidemic diarrhea virus (PEDV), recombinant spike (S12), nucleocapsid (N), and whole viral (WV) proteins, for the detection of IgG and IgA antibodies in colostrum and milk and to evaluate the diagnostic sensitivity (DSe) and diagnostic specificity (DSp) of the assay as a diagnostic method. Colostrum (n = 347) and milk (n = 272) samples from sows were employed in this assay. Indirect ELISA based on three coating antigens was assessed by receiver operating characteristic (ROC) curve analysis with a virus neutralization (VN) test as a reference method, and the cutoff value for calculating DSe and DSp was determined.

Evolutionary and epidemiological analyses based on spike genes of porcine epidemic diarrhea virus circulating in Thailand in 2008-2015.

Porcine epidemic diarrhea (PED) has been endemic causing sporadic outbreaks in Thailand since 2007. In 2014-2015, several herds had experienced severe PED outbreaks and the reason of the re-current outbreaks was unknown. Whether or not the introduction of exotic strains or continual evolution of existing PEDV, genetic analyses would provide a more understanding in its evolutionary pattern.

The genetic diversity and complete genome analysis of two novel porcine deltacoronavirus isolates in Thailand in 2015.

Porcine deltacoronavirus (PDCoV) was identified in intestinal samples collected from piglets with diarrhea in Thailand in 2015. Two Thai PDCoV isolates, P23_15_TT_1115 and P24_15_NT1_1215, were isolated and identified. The full-length genome sequences of the P23_15_TT_1115 and P24_15_NT1_1215 isolates were 25,404 and 25,407 nucleotides in length, respectively, which were relatively shorter than that of US and China PDCoV.

Humoral immune responses and viral shedding following vaccination with modified live porcine reproductive and respiratory syndrome virus vaccines.

The antibody response and pattern of shedding of vaccine virus following vaccination with modified live genotype I or II porcine reproductive and respiratory syndrome virus (PRRSV) vaccines (MLVs) were investigated. Ninety PRRSV-free pigs were divided randomly seven, groups including the NEG, EU1, EU2, US1, US2, US3 and US4 groups. The NEG group was unvaccinated.

The first detection and full-length genome sequence of porcine deltacoronavirus isolated in Lao PDR.

Porcine deltacoronavirus (PDCoV) has been reported in many countries, including Hong Kong, the United States, South Korea, China and Thailand. In January 2016, clinical diarrhea similar to that of porcine epidemic diarrhea virus (PEDV) with a lower mortality rate was reported on a swine farm in Lao PDR. Intestine samples were collected from 3-day-old pigs with clinical diarrhea and assayed for the presence of swine enteric coronaviruses.

Full-length genome analysis of two genetically distinct variants of porcine epidemic diarrhea virus in Thailand.

Porcine epidemic diarrhea virus (PEDV) has continued to cause sporadic outbreaks in Thailand since 2007 and a pandemic variant containing an insertion and deletion in the spike gene was responsible for outbreaks. In 2014, there were further outbreaks of the disease occurring within four months of each other. In this study, the full-length genome sequences of two genetically distinct PEDV isolates from the outbreaks were characterized.

Complete Genome Sequence of Porcine Deltacoronavirus Isolated in Thailand in 2015.

In Thailand, porcine deltacoronavirus (PDCoV) was first identified in November 2015. The virus was isolated from piglets experiencing diarrhea outbreak. Herein, the full-length genome sequence of the Thai PDCoV isolate P23_15_TT_1115 is reported.

Complete Genome Sequences of Two Genetically Distinct Variants of Porcine Epidemic Diarrhea Virus in the Eastern Region of Thailand.

Porcine epidemic diarrhea virus (PEDV) has continued to cause sporadic outbreaks in Thailand since 2007. Previously, PEDV in Thailand was a new variant containing an insertion and deletion in the spike gene. Herein, full-length genome sequences are reported for two variants of PEDV isolates from pigs displaying diarrhea in Thailand.

Complete genome characterization of porcine epidemic diarrhea virus in Vietnam.

Porcine epidemic diarrhea virus (PEDV) first emerged in Vietnam in 2009. In this study, the complete genomes of three Vietnamese PEDV isolates were characterized. These three isolates were isolated from 3-day-old pigs experiencing diarrhea.

Dynamics and evolution of highly pathogenic porcine reproductive and respiratory syndrome virus following its introduction into a herd concurrently infected with both types 1 and 2.

Since its first emergence in Thailand in late 2010, highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) has caused sporadic outbreaks on Thai swine farms. The objective of this study was to investigate the dynamics and evolution of PRRSV in a herd experiencing an HP-PRRSV outbreak. Following its introduction, HP-PRRSV caused severe outbreaks and subsequently established persistent infection in the herd, resulting in the emergence of a novel cluster of type 2 (North American, NA) isolates.

Genetic diversity of ORF3 and spike genes of porcine epidemic diarrhea virus in Thailand.

Porcine epidemic diarrhea virus (PEDV) has become endemic in the Thai swine industry, causing economic losses and repeated outbreaks since its first emergence in 2007. In the present study, 69 Thai PEDV isolates were obtained from 50 swine herds across Thailand during the period 2008-2012. Both partial and complete nucleotide sequences of the spike (S) glycoprotein and the nucleotide sequences of ORF3 genes were determined to investigate the genetic diversity and molecular epidemiology of Thai PEDV.

Dynamics and evolution of porcine reproductive and respiratory syndrome virus (PRRSV) ORF5 following modified live PRRSV vaccination in a PRRSV-infected herd.

The objective of this study was to investigate the dynamics and evolution of porcine reproductive and respiratory syndrome virus (PRRSV) ORF5 following the use of a modified live PRRSV (MLV) vaccine. A PRRSV-positive farm with coexistence of types 1 and 2 and no history of MLV vaccination was investigated. Vaccination with a type 2 MLV (Ingelvac PRRS MLV, Boehringer Ingelheim, USA) was implemented.

Genetic diversity of the ORF5 gene of porcine reproductive and respiratory syndrome virus (PRRSV) genotypes I and II in Thailand.

To investigate the genetic diversity of porcine reproductive and respiratory syndrome virus (PRRSV) in Thailand, 279 ORF5 sequences of PRRSV collected during 2010-2011 from 102 swine herds in five swine-producing areas were analyzed. The co-existence of European (EU) and North American (NA) genotypes was observed in 98 % of herds investigated and was evident at the pig level. Both genotypes have evolved separately with a temporal influence on strain development.

Porcine reproductive and respiratory syndrome virus, Thailand, 2010-2011.

Characterization of porcine reproductive and respiratory syndrome virus (PRRSV) isolates from pigs in Thailand showed 30-aa discontinuous deletions in nonstructural protein 2, identical to sequences for highly pathogenic PRRSV. The novel virus is genetically related to PRRSV from China and may have spread to Thailand through illegal transport of infectious animals from bordering countries.