1

Speaker(s)：

Mim-Shinh, Lee

Topic

Multiple Subtypes of Highly Pathogenic H5 Avian Influenza Virus Detected in Geese in Taiwan.

Abstract

In January 2015, three NA (nauraminidase) subtypes of highly pathogenic H5 avian influenza virus (HPAI), including H5N2, H5N3 and H5N8, were detected from goose farms in Taiwan. In this wave of outbreaks, 90% goose farms were confirmed as HPAI infection and the culling policy was applied to prevent further spread of the disease. To date, all the HPAI cases spread across 12 counties, from Taoyuan to Pingtung , in west coast of Taiwan except one case in east coast (Taitung). Among them, Yunlin and Pingtung County have suffered the most severe losses in particular. For pathogenicity analysis of isolated viruses in Taiwan, the results revealed that amino acid sequences near HA(hemagglutinin) cleavage site are PLRERRRKR * GLF, and containing multiple basic amino acids is a unique characteristic of HPAI viruses. Phylogenetic analysis of HA & MP genes of these viruses indicated they originated from H5N8 virus strains isolated in China during 2010-2013, were also and the most similar to the Japanese and North American virus isolates. In addition, 2 to 6 segments of Taiwan isolates were re-assorted from other strain, and formed H5N2, H5N3, H5N8 subtypes of HPAI respectively. Nevertheless, all the genes of these viruses are clustered in Eurasian lineage, but they are different from North American H5N2, H5N8, H5N1 isolates mixed with Eurasian and American lineages.

2

Speaker(s)：

Chun Wang

Topic

Detection of Antibody for Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) and the Visit Report to the OIE Refer Laboratory of PRRSV

Abstract

Porcine reproductive and respiratory syndrome virus virus (PRRSV) is most important swine viral pathogen. According to the World Organisation for Animal Health (OIE) specification terrestrial animal diagnostic tests and vaccines manuals, serological diagnosis of PRRSV could be performed using several methods, including enzyme linked immunosorbent assay (ELISA), indirect immunofluorescense assay (IFA), immunoperoxidase monolayer assay (IPMA), and neutralizing antibody assays (SNT) pigs to determine serum antibody titers. Since the neutralizing antibody detection method is easy to use, low cost and other advantages, SNT is applied to the current epidemiological surveillance PRRSV.

In 2015, OIE has been holds PRRS and other swine disease diagnosis workshop in PRRS reference laboratory (Regional Hands-on Laboratory Training on PRRS and Other Swine Disease Diagnosis) in Beijing. Many members from East Asia have been participated this workshop, including Mongolia, Cambodia, Myanmar, Vietnam, Laos, Malaysia, Philippines, Thailand, Indonesia and Taiwan. China Animal Disease Control Center (CADCC) sent several lecturers and conducted a number of diagnostic techniques for the PRRS and other swine viral pathogens, including cell culture, virus isolation, serological testing and real-time PCR. During the workshop, each member has been issue country report, including brief national swine disease diagnostic systems and main constraints. The PRRS diagnostic techniques will be enhanced by attend this workshop, and understand the trends of swine disease research of East Asia as a reference on our pig disease prevention. In addition, the cooperation friendship will be established each other and thus protect our livestock industry.

3

Speaker(s)：

Tsu Han Chen

Topic

Optimisation and validation of antibody detection assays for differentiation of infected from vaccinated animals against Foot-and-mouth disease virus

Abstract

Foot-and-mouth disease (FMD), swine vesicular disease (SVD), vesicular stomatitis (VS), and vesicular exanthema (VE) are highly contagious vesicular animal diseases, and they are not able to be differentiated clinically from each other. For the purpose of instant detecting FMD and differentiating it from the other vesicular diseases, many methods have been developed and evaluated in recent years. The in-house in-vitro diagnostic devices (IVDs) were developed by our institute, including the chromatographic strip, sandwich ELISA, blocking ELISA, singleplex Luminex, and multiplex Luminex (xMAP). The non-structural protein 3ABC gene of FMDV O/TW/1999 was cloned into expression vector, which was based on an Escherichia coli expression system. The expressed protein was employed to develop the complex interface measurement platforms for FMDV tests. Strip and plate and microsphere formats were developed and evaluated for their abilities in detecting serum antibodies against non-structural protein (NSP-3ABC) of the FMDV. The tests were based on the World Organization for Animal Health Terrestrial Manual 2013, chapter 1.1.5. and National Association of Testing Authorities Australia 2004. Almost perfect agreement between the results from in-house methods and those from the 3ABC blocking ELISA, and 3B peptide indirect ELISA kits were obtained. Moreover, antibodies to nonstructural proteins of the serotypes O, A, C, Asia 1, SAT 1, SAT 2 and SAT 3 were also detected in sera of infected cattle. These studies were showed that the sensitivity and specificity of the methods were higher than 85%, which can be as references for diagnosis and assessment of the immune status. Furthermore, the specificities of these assays were highlighted by the absence of cross-reactions generated by antibodies against the SVDV and VSV at different titers.

4

Speaker(s)：

Chun-Hsien Tseng

Topic

Sequence and Pathogenesis Analysis of Taiwan Ferret-Badger Rabies Virus

Abstract

Taiwan had been listed as a rabies-free region since 1961, and was also one of the limited rabies-free countries in the world until the deadly disease was confirmed in Formosan ferret-badgers in July, 2013. There have been total 462 diagnosed cases in ferret-badger, 1 in shrew,1 in puppy, and 5 in gem-faced civet. Ferret-badgers are currently major infection animals and the disease reservoirs in Taiwan. Based on the phylogenetic analysis results, Taiwan ferret-badger rabies virus has evolved into an independent group and existed in the ferret-badger population for 50-100 years. This appears the virus strain has adapted to ferret-badgers. Although rabies is a virus known to affect all the homoeothermic animals with foreign experts’ experiences of rabies research, it suggests the pathogenicity of a rabies virus adapted to a specific animal species could vary with different animal species. In addition, the suspension samples prepared from salivary glands and brains of field-infected ferret-badgers were inoculated into 3-4 weeks old mice intracranially for virus titration, and all the virus titers were about 10^2.5micLD₅₀/mL. For following pathogenesis investigation with the virus suspensions, the incubation period through intracranial route was approximately 2 weeks, and the disease course was as long as 2-5 weeks. As to intramuscular inoculation with virus titers of 10^1.5mic LD₅₀/mL, no clinical symptoms showed in all mice after 180 days observation. All the fluorescence-antibody staining of the mouse brain samples demonstrated negative results.

5

Speaker(s)：

Shu-Chia Hu

Topic

Oversea trainings for lyssavirus antibody tests and biorisk management

Abstract

The training of serological testing for lyssavirus was performed at the Poxvirus and Rabies branch of Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, USA in March, 2015. Courses and practices for laboratory biosafety, lyssavirus antibody test (rapid fluorescent focus inhibition test (RFFIT) and micro-RFFIT), and blind testing were scheduled during the three-week technical visit. Bat sera sampled in Taiwan were also tested during the courses.

The second training “Biorisk management training course” was held at Australian Animal Health Laboratory (AAHL) in Geelong, Victoria, Australia in April. This training was the second stage of “Bat Born Virsu Surveillance Workshop”. Specific topics including biosecurity awareness, hazard identification and risk assessment, incident and spill response, effective sterilization of laboratory waste were dealt with in the workshop. The participants were allowed to visit P3 laboratories and animal houses of the AAHL. In addition to lectures, sterilizing of laboratory waste, operating centrifuges, practicing the respirator fit test, and wearing P4 positive pressure suit were also performed