U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 Exotic & Emerging Avian Viral Diseases Research: Athens, GA
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                People

                    Staff Listing
                                    Careers


        


                    USNPRC
                        Richard B Russell Center
                                    Southeast Poultry Research Center
                                    Return to USNPRC home page
                    Research Units at USNPRC
                        Quality and Safety Assessment Research
                                    Poultry Microbiological Safety and Processing Research
                                    Toxicology and Mycotoxin Research
                                    Egg and Poultry Production Safety Research Unit
                                    Exotic and Emerging Avian Viral Diseases
                                    Endemic Poultry Viral Diseases Research
                                    Avian Diseases and Oncology Research
                                    Return to USNPRC home pageSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Southeast Area Athens, Georgia U.S. National Poultry Research Center Exotic & Emerging Avian Viral Diseases Research Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            Kapczynski, Darrell
  Submitted to: Meeting Abstract
                                    Publication Type: Abstract Only
                                    Publication Acceptance Date: 12/20/2013
                                    Publication  Date: N/A
                                    Citation: N/AInterpretive Summary:
                                Technical Abstract: Vaccination of poultry has been used for decades and is a common practice in integrated poultry production. However, the decision to use vaccination for protection against avian influenza (AI) is typically dependent on several factors including pathotype, type of birds and eradication strategies. The recent outbreaks in poultry of AI H7N3 in Mexico and H7N9 in China underscore the need for continued research in vaccine countermeasures as part of an eradication effort. However, these two outbreaks contrast the use for vaccines as one involves infection of commercial egg-laying birds (H7N3) and the other is primarily found in live bird markets (H7N9) but with human health implications.
 
In June of 2012, an outbreak of highly pathogenic avian influenza (HPAI) H7N3 was reported in egg-laying hens in Jalisco, Mexico. Since that time the virus has spread to many surrounding States and new outbreaks continue to be reported with millions of birds depopulated. Vaccine trials were performed to determine protective efficacy of an inactivated H7 vaccine. In the first set of experiments, a Mexican-lineage low pathogenic AI (LPAI) H7N3 was applied to 2 week-old chickens. When challenged, vaccinated birds demonstrated 100 % protection. In a second experiment, 26 week-old egg-laying hens were vaccinated and challenged against the HPAI virus. All vaccinated birds reduced shedding of virus compared to sham vaccinated birds. Vaccinated birds were also protected against drops in egg production. These results demonstrate the LPAI vaccine isolate can provide protection against the HPAI H7N3 virus.

In March of 2013, the first cases of H7N9 were reported in humans and shortly thereafter the virus was isolated from pigeon and poultry in live bird markets. The genetic composition of these H7N9 viruses appears to be solely of avian origin, although of low pathogenicity (LP). Although few isolations of these viruses have been demonstrated on poultry farms, the correlation between live bird market shut downs and reduced human infections in China underscores a linkage between poultry and humans. In response to the outbreak, vaccine efficacy trials were recently performed to determine if inactivated H7N9 vaccine could increase resistance of birds to clinical disease and shedding of virus. A homologous H7N9 vaccine was formulated into an inactivated emulsion and injected at various doses into 3 week old SPF birds. Birds were challenged at 6 weeks of age with 108 EID50 per bird delivered via intranasal route. Sham vaccinated birds demonstrated 10 % mortality and reduction in weight gain. In contrast vaccinated groups demonstrated improved weight gain compared to sham vaccinated birds. Taken together, these results indicate that the homologous vaccine can provide protection to poultry against this recent LPAI H7N9 virus.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov