The threat of animal influenza viruses
Deartment Hog Cholera Research
Ming-Shiuh Lee
Abstract
In humans, the infection of influenza A or B viruses manifests typically as an acute and self-limited upper respiratory tract illness characterized by fever, cough, sore throat, and malaise. However, influenza can present different clinical signs, ranging from sub-clinical or even asymptomatic infection to a severe primary viral pneumonia. Influenza A viruses (IAVs) are considered to be one of the greatest threats for the next global pandemic due to the abundance of permanent animal reservoirs harboring viruses that occasionally spill over into humans. Pandemic influenza viruses arise from reassortment, the creation of a genetically and antigenically new virus by “mixing-and-matching” viral genes from human and/or animal influenza viruses. These “antigenic shift” events introduce an immunologically novel influenza virus into the human population, which has no pre-existing immunity to it. Sixteen antigenically distinct HA and nine NA subtypes exist in wild aquatic birds, which are considered to be the reservoir hosts for IAV diversity. Only a few of these subtypes have successfully crossed into other avian and mammalian hosts. The first outbreak of avian influenza A(H5N1) virus in humans occurred in Hong Kong in 1997. In 2013, the first human case of infection with avian influenza A (H6N1) virus was reported in Taiwan. The avian influenza A H7N9 virus has caused infections in human beings in China since 2013. A large epidemic in 2016-2017 prompted concerns that the epidemiology of the virus might have changed, increasing the threat of a pandemic.
The Implementation of the Collaboration Activities with Nancy Laboratory for Rabies and Wildlife, France and Learning Operation Model of an OIE Laboratory
Ai-Ping Hsu
Abstract
The collaboration Memorandum of Understanding (MOU) was signed between Animal Health Research Institute (AHRI) and Nancy Laboratory for Rabies and Wildlife, France (Nancy lab.) in 2014. Nancy lab. further assisted AHRI in establishing the fluorescent antibody virus neutralization test (FAVN) for rabies serology diagnosis; in addition, the efficacy and safety of OIE-recommended SAG2 rabies oral vaccine in ferret badgers has been evaluated collaboratively, and satisfactory results have been proved. In order to continue and broaden the preliminary collaboration, Nancy lab. proposed the OIE Twinning Project conducted jointly to assist AHRI to be qualified as an OIE Reference laboratory for rabies. Thus, AHRI sent a researcher to Nancy laboratory for practical training. The goals of this training project include: learning animal experiments for continuous collaboration of pathogenicity study on Taiwan ferret badger rabies virus in France, training on laboratory quality management system, and doing an oral presentation in a workshop hold by Nancy lab. to gain AHRI publicity. During the period in France, the proposed plan the OIE Twinning Project was also written completely.
Study on Pathogenesis of in PRRSV strains isolated in Taiwan
Deng, Ming-Chung
Associate Researcher, Division of Hog Cholera research
Abstract
Porcine Reproductive and Respiratory Syndrome (PRRS) is one of the most economically important diseases in pig production worldwide. PRRS is also a severe problem in pig farms of Taiwan. The PRRS pathogen is a single strand RNA virus with envelope, classified in the family Arteriviridae within the order Nidovirales. The PRRS virus gene exhibits mutation and recombination; therefore, two different genotype, North American (NA) and European (EU) types, exist in the world.According the genome analysis, all of isolated strains in Taiwan were belonged to the NA type. In order to understand the pathogenesis of Taiwan isolated strains, we selected four PRRS viruses including NA reference strain VR-2332, original Taiwan isolated strain WSV and current Taiwan isolated strain SH2,1214 and 3267, to implement the animal challenge test for the virulence assessment.This study presented a significant difference in pathological change, but there were no difference in antibody titer, growth rate and viral load in infected pigs. However, the animal challenge test is still a useful model to assess the virulence of different isolated strains according the gross lesion induced by virus inoculation.