Maximising infectious bronchitis virus vaccine efficacy
From Poultry Hub
Maximising infectious bronchitis virus (IBV) vaccine efficacy was the focus of a Poultry CRC research project, Diagnostics and surveillance of infectious bronchitis. The following information is derived from the project's Final Report.
Contents |
Fighting off NSW variant strain N4/02
The novel NSW variant strain N4/02 of IBV has been identified as a mild respiratory strain, causing subclinical infection in the absence of any secondary infection (Sapats, 2008). Deaths amongst flocks associated with N4/02 are most likely caused by secondary infections, for example, avian pathogenic E. coli.
Protection afforded by existing vaccines
Vaccinating with the S vaccine at hatch and again at day 14 provides 53% protection. This is the maximum efficacy achievable using combinations of existing vaccines (S, I, Vic S and A3). Vaccinating with the S vaccine at hatch and using N4/02 as a vaccine at day 14 provides 100% protection against N4/02 itself and 93 and 100% protection against variant strains N1/88 and Q3/88, respectively (Sapats, 2008).
N4/02 as a vaccine
The N4/02 variant strain has the potential to be developed as a vaccine for use in conjunction with the S vaccine to provide broad cross protection against other variant strains of IBV (Sapats, 2008). However, the currently restricted potential market for an N4/02 vaccine prevents commercial development due cost of research and registration.
Continued surveillance of IBV strains circulating in the field
Surveillance of IBV strains circulating in the field will continue through industry veterinarians communicating with the International Avian Health Laboratory, Asia Pacific Centre for Animal Health located at The University of Melbourne’s School of Veterinary Science. If investigation of genetic changes occurring in field isolates of N4/02 or other IBV variant strains is required, personnel and resources remain available at the Australian Animal Health Laboratory, CSIRO, to conduct appropriate research.
Further information
For further information, contact Dr Sandra Sapats at CSIRO Livestock Industries, Associate Professor Amir Noormohammadi at The University of Melbourne, or the Australian Poultry CRC. Information in this article is based on the following Final Report:
- Sapats, S (2008) Control of Infectious Bronchitis Virus: Improved diagnostics and disease surveillance through the application of genomic technology, Final Report ISBN 1 921010 17 7, Australian Poultry CRC
See also
- Infectious bronchitis
- Research project: Diagnostics and surveillance of infectious bronchitis
- Research project: Transfer of diagnostic technologies to core diagnostic facility for the benefit of the Australian poultry industry
- Research project: Development of a real-time PCR test to quantify infectious bronchitis virus in tissues of chickens
- Vaccines
External links
- Infectious-bronchitis.com is the first peer reviewed website with a specific focus on Infectious Bronchitis in chickens.
- The Merck Veterinary Manual has a section dedicated to Poultry
- ThePoultrySite.com's Poultry Disease Guide
