1

Speaker(s)：

Kuo-Jung Tsai

Topic

Rabies infection of ferret badger in Taiwan in 2013

Abstract

A huge amount of dead wild carnivores have been sent to Animal Health Research Institute, Council of Agriculture, Executive Yuan for rabies diagnosis after the rabies diagnoses for the initial three ferret badgers were confirmed, by the end of July of 2013 in Taiwan. A total of 2,846 brain samples were tested for rabies using direct immunofluorescence assay. A total of 285 brains of ferret badger were shown positive reaction. The rabid badgers were collected from 9 counties including Taitung, Nantou, Taichung, Tainan, Kaohsiung, Yunlin, Chiayi, Pingtung and Hualien. Genomic sequencing of rabies virus was conducted for phylogenetic analysis. Preliminary results indicate that rabies affecting Taiwanese ferret badgers were categorized into three subgroups within an independent lineage.

2

Speaker(s)：

Yu-Pin Liu

Topic

Surveillance of Avian Influenza in Imported and Smuggled Avian Species

Abstract

Birds carrying avian influenza virus(AIV) in the case of importation and smuggling are increasing attention to the risk of domestic poultry disease prevention and public health. In this study, 432 lots of imported birds and 210 lots of smuggled birds were submitted to AHRI for the surveillance of AIVs from 2007 to 2013. H3N8 viruses were isolated from two lots of smuggling avian species from China in 2008 and 2010 respectively. High-pathogenicity H5N1 viruses were isolated from one lot of 38 Japanese white-eyes that were smuggled to Taiwan from Macao in 2012. The H5N1 virus had multiple basic amino acid residues at the cleavage site (PQRERRRKR*GLF). The AIVs were not isolated and detected in any lot of imported birds. The presence of the H5N1 influenza virus in smuggling birds demonstrats the potential risk to public health even in countries where the virus is not enzootic and represents a possible source of influenza outbreaks in poultry.

3

Speaker(s)：

Chia-Yi Chang

Topic

Antigen variation of E2 glycoprotein among different genotypes CSFV influence the efficacy of the CSFV vaccines

Abstract

Classical swine fever (CSF) is an economically important, highly contagious disease of swine worldwide. CSF is caused by classical swine fever virus (CSFV), and circulates in domestic pigs and wild boars. There are two main strategies to control CSF, including systematic prophylactic vaccination and non-vaccination stamping-out policy. Although modified live vaccines (MLV) provide earlier and more complete protection than E2 subunit vaccines, it has the drawback of not allowing differentiation between infected and vaccinated animals (DIVA). The aim of the study is to investigate whether the antigenic variations among various genotypes of CSFV influence the efficacy of the MLV and E2 subunit vaccines. The cross-neutralization antibodies were analyzed against CSFV strains of genotypes 1.1, 2.1 and 3.4 using (1) CSFV genotype-specific antisera from pigs experimentally infected with genotype 1.1, 2.1 or 3.4 strain and (2) E2 genotype-specific antisera from pigs immunized with recombinant E2 protein of genotype 1.1, 2.1 or 3.4 strain. The results indicated that antibodies raised by either live virus or E2 protein which neutralize genotypically homologous strains better than heterologous ones. However, although this is not a major concern for MLV as the induced immune responses can protect pigs against the challenge of various genotypes of CSFVs, it is critical for E2 subunit vaccines. It is thus necessary to evaluate whether the E2 subunit vaccine can completely protect against the current prevalent strains in the field.