Development of a novel real-time PCR assay targeting p54 gene for rapid detection of African swine fever virus (ASFV) strains circulating in Vietnam.

African swine fever (ASF) continues to cause outbreaks throughout regions of Africa, Europe and Asia. The disease can cause severe morbidity and mortality resulting in serious economic losses. Since there is no vaccine available to control ASF, early detection is critical to contain and control the disease.

Comparing recombinant MPB70/SahH and native 20-kDa protein for detecting bovine tuberculosis using ELISA.

Bovine tuberculosis (bTB) is a zoonosis caused by Mycobacterium bovis. Test-and-cull protocols and gross pathological examinations of abattoir animals as well as milk pasteurization have been implemented to prevent the spread of tuberculosis from animals to humans worldwide. Despite the importance of precise and rapid diagnostic tests, conventional methods including intradermal skin tests and γ-interferon assays are limited by the high rate of false-negative results for cattle in the late infectious stage and due to laborious and time-consuming procedures.

O/SEA/Mya-98 lineage foot-and-mouth disease virus was responsible for an extensive epidemic that occurred in late 2018 in Vietnam.

Since late 2018, foot-and-mouth disease (FMD) has reemerged and rapidly swept through pig farms in North and Central Vietnam, despite widespread use of commercial FMD vaccines. To investigate the FMD virus (FMDV) strains responsible for the current epidemics, 40 FMDV samples were collected from 17 provinces during November-December 2018, and the VP1 coding genes were sequenced and analyzed. Phylogenetic analysis and sequence comparisons revealed that all of the reemerging Vietnamese FMDVs belonged to the Mya-98 lineage of the O/Southeast Asia topotype (O/SEA/Mya-98) and shared high nucleotide (99.

Outbreak of African Swine Fever, Vietnam, 2019.

African swine fever is one of the most dangerous diseases of swine. We confirmed the 2019 outbreak in Vietnam by real-time reverse transcription PCR. The causative strain belonged to p72 genotype II and was 100% identical with viruses isolated in China (2018) and Georgia (2007).

Prolonged shedding of the canine influenza H3N2 virus in nasal swabs of experimentally immunocompromised dogs.

Purpose: The avian origin canine influenza virus H3N2 has been recently isolated and found to be currently in dog population in South Korea and China. The purpose of this study was to clarify the relationship between immunosuppressive glucocorticoids used in veterinary clinical practice and viral shedding pattern of influenza in dogs.

Materials And Methods: Eight conventional beagle dogs were divided into control infection group and immunocompromised group.

Usefulness of a Helicobacter pylori stool antigen test for diagnosing H. pylori infected C57BL/6 mice.

Among several diagnostic tests, a Helicobacter pylori stool antigen (HpSA) test may offer a useful noninvasive method for diagnosing infection without sacrificing animals. In this study, male C57BL/6 mice (n=6) were infected with H. pylori ATCC 49503 (1×10(8) CFU/mouse) by intragastric inoculation three times at 2-day intervals, and H.

A novel reassortant canine H3N1 influenza virus between pandemic H1N1 and canine H3N2 influenza viruses in Korea.

During recent canine influenza surveillance in South Korea, a novel H3N1 canine influenza virus (CIV) that is a putative reassortant between pandemic H1N1 2009 and H3N2 CIVs was isolated. Genetic analysis of eight genes of the influenza virus revealed that the novel H3N1 isolate presented high similarities (99.1-99.

Association between nasal shedding and fever that influenza A (H3N2) induces in dogs.

Background: Avian origin canine influenza virus was reported in Korea. The dog to dog contact transmission of the avian origin canine influenza virus (CIV) H3N2 and CIV H3N8 was shown by experimental contact transmission. This study was focused on viral excretion and fever in order to elucidate the epidemiological associations which might be helpful to control the disease transmissions in CIV outbreak in dogs.

A serological survey of canine respiratory coronavirus and canine influenza virus in Korean dogs.

The relationship between canine respiratory coronavirus (CRCoV) and canine influenza virus (CIV) seropositivity in dogs in Korea was examined. Sixty-two of the 483 samples (12.8%) were seropositive for CRCoV by indirect fluorescent antibody (IFA) analysis.

Validation of egg yolk antibody based C-ELISA for avian influenza surveillance in breeder duck.

Active surveillance for avian influenza virus (AIV) has expanded from chicken to various poultry species including duck. To further effective antibody screening in laying breeder ducks, we validated the egg yolk antibody as alternative source to serum for AIV antibody. Sera and eggs were collected at weekly intervals after two types of AIV vaccination, H5N3 and H9N2.

Comparative measurement of cell-mediated immune responses of swine to the M and N proteins of porcine reproductive and respiratory syndrome virus.

The principal objectives of this study were to develop autologous antigen-presenting cells (APCs) and to characterize the antigen-specific T-cell responses to the M and N proteins of porcine reproductive and respiratory syndrome virus (PRRSV) by using those APCs in outbred pigs. The orf6 and orf7 genes fused with porcine granulocyte-macrophage colony-stimulating factor (GM-CSF) were cloned into the mammalian expression vector to generate two plasmid DNAs, namely, pcDNA3.1-GM-CSF-PRRSV-M and pcDNA3.

Elevated serum levels of S100 calcium binding protein A8 (S100A8) reflect disease severity in canine atopic dermatitis.

A monoclonal antibody to canine S100 calcium binding protein A8 (S100A8) was developed to determine the association between S100A8 and the disease severity of canine atopic dermatitis. Serum S100A8 concentrations were studied in dogs with canine atopic dermatitis (n=213) and healthy dogs (n=213). Statistical correlations between these indices and atopic dermatitis activity were established, and dermatitis severity was assessed according to the CADESI score.

Protective efficacy and immunogenicity of an inactivated avian-origin H3N2 canine influenza vaccine in dogs challenged with the virulent virus.

Transmission of avian-origin influenza A virus (H3N2) to dogs had been reported and since then the H3N2 virus infection across South Korea has been occurred repeatedly in the country's animal clinics and kennels. Dog-to-dog transmission of the virus had also been experimentally demonstrated by direct contact. In this study, immunogenicity and protective efficacy against challenge exposure of the formalin-inactivated H3N2 influenza virus vaccine with a synthetic polymer adjuvant was investigated in dogs.

Development and validation of an immunogold chromatographic test for on-farm detection of PRRSV.

An immunochromatographic test strip was developed to detect porcine reproductive and respiratory syndrome virus (PRRSV). The test uses two gold-labeled monoclonal antibodies: D5 against recombinant nucleocapsid protein (rN) and E9 against recombinant M protein (rM). In the test, PRRSV binds to a mixture of D5 and E9 labeled with colloidal gold; the complexes move through a membrane and are captured by rabbit anti-rM and anti-rN antibodies at a test line, producing a reddish-purple band because of the increased concentration of gold.

A serological survey of avian origin canine H3N2 influenza virus in dogs in Korea.

Canine H3N2 influenza viruses of avian origin were recently isolated and found to induce disease in dogs. Results of serologic analysis indicate that avian origin canine influenza virus can spread rapidly through local dog populations, which indicates its potential for becoming established in dogs throughout Korea.

Experimental infection of dogs with avian-origin canine influenza A virus (H3N2).

Susceptible dogs were brought into contact with dogs experimentally infected with an avian-origin influenza A virus (H3N2) that had been isolated from a pet dog with severe respiratory syndrome. All the experimentally infected and contact-exposed dogs showed elevated rectal temperatures, virus shedding, seroconversion, and severe necrotizing tracheobronchitis and bronchioalveolitis.

A simple and rapid immunochromatographic strip test for detecting antibody to porcine reproductive and respiratory syndrome virus.

Porcine reproductive and respiratory syndrome is rapidly gaining worldwide importance as one of the most economically significant diseases of swine. The antibody of Porcine reproductive and respiratory syndrome virus (PRRSV) is detected currently by the combined use of an enzyme-linked immunosorbent assay, serum neutralization test, immunoperoxidase monolayer assay, indirect immunofluorescent antibody test. These methods are time-consuming and require specialized equipment operated by trained technicians.

Transmission of avian influenza virus (H3N2) to dogs.

In South Korea, where avian influenza virus subtypes H3N2, H5N1, H6N1, and H9N2 circulate or have been detected, 3 genetically similar canine influenza virus (H3N2) strains of avian origin (A/canine/Korea/01/2007, A/canine/Korea/02/2007, and A/canine/Korea/03/2007) were isolated from dogs exhibiting severe respiratory disease. To determine whether the novel canine influenza virus of avian origin was transmitted among dogs, we experimentally infected beagles with this influenza virus (H3N2) isolate. The beagles shed virus through nasal excretion, seroconverted, and became ill with severe necrotizing tracheobronchitis and bronchioalveolitis with accompanying clinical signs (e.

Evaluation of a rapid immunodiagnostic test kit for rabies virus.

A rapid immunodiagnostic test kit for rabies virus detection was evaluated using 51 clinical samples and 4 isolates of rabies virus. The quick detection of rabies virus under field conditions may be helpful in determining if post-exposure prophylaxis is needed, thereby avoiding unnecessary treatments, as well as undue economic burden. There are several widely used diagnostic methods for rabies, including fluorescent antibody tests, reverse transcription polymerase chain reaction, and electron microscopy; however, these methods include time-consuming, intricate, and costly procedures.

Serologic surveillance of swine H1 and H3 and avian H5 and H9 influenza A virus infections in swine population in Korea.

Influenza A is a respiratory disease common in the swine industry. Three subtypes, H1N1, H1N2 and H3N2 influenza A viruses, are currently co-circulating in swine populations in Korea. An outbreak of the highly pathogenic avian influenza H5N1 virus occurred in domestic bird farms in Korea during the winter season of 2003.

One-step immunochromatography assay kit for detecting antibodies to canine parvovirus.

This study was performed to determine the feasibility of using whole serum to detect antibodies to canine parvovirus (CPV) under nonlaboratory conditions and to evaluate the performance characteristics of an immunochromatography assay kit. Precise detection of levels of antibody against CPV in puppies can be used to determine a vaccination schedule, because maternal antibodies frequently result in the failure of protective vaccination, and can also be used to determine the antibody levels of infected puppies. Several methods for the titration of CPV antibodies have been reported, including the hemagglutination inhibition (HI) assay, which is considered the "gold standard.

Use of an internal control in a quantitative RT-PCR assay for quantitation of porcine epidemic diarrhea virus shedding in pigs.

Porcine epidemic diarrhea virus (PEDV), a member of the family Coronaviridae, has caused a devastating enteric disease in the Korean swine industry. Previously, the differences between virulent field PEDV strains and a Vero cell culture adapted PEDV DR13 strain were determined using restriction fragment length polymorphism analysis (RFLP), and PEDV shedding patterns in pigs were reported. In an extension to these studies, an internal control was constructed and quantitative analysis of virus shedding after oral inoculation was established.