making LT protection safer and easier

making LT protection safer and easier 1 vaccine up to 3 immunities

4 Vectormune FP-LT and. Vectormune FP-LT is a genetically engineered live fowl pox virus vaccine carrying 2 immunorelevant genes from LT virus (Figure 3). 1 Facts of infectious laryngotracheitis (LT) in chickens It s a highly infectious disease of worldwide distribution. It induces significant economic losses due to high morbidity and variable mortality, drop in egg production, weight loss and susceptibility to other respiratory infections. The disease is caused by a Herpes viral infection characterized by latency, persistency and reversion to virulence. The viral infection induces chronic carrier for life, allowing the transmission to other birds and environmental contamination. Figure 3: Illustration showing the insertion of 2 LT virus genes into the fowl pox viral genone resulting in a live fowl pox virus vectored LT contained in Vectormune FP-LT vaccine. + = Figure 1: 2 The diagnosis can be done by suffocation Clinical signs (Figure 1) Post-mortem lesions: they may vary from mild to severe (Figure 2) Histopathology: observations of typical giant cells and intranuclear inclusion bodies in the tracheal epithelium in the early stage of infection Virus isolation Molecular biology methods to detect viral DNA such as PCR Serology Other diagnostic methods such as immunohistochemistry Figure 2: and immunofluorescence laryngotracheitis virus FOWL POX VIRUS Vectormune FP-LT vaccine This vaccine is combining the safety of a fowl pox vaccine with the protection induced by specific proteins from LT field virus. Vectormune FP-LT is able to induce a high level of protection against both ILT and fowl pox viruses. severe laryngotracheitis The vaccine is available in 2 combinations: for fowl pox and LT protection 3 Current live LT (CEO: Chicken Embryo Origin or TCO: Tissue Culture Origin) vaccines situation 9 O. Langlois There is a need for a new protective and safe LT vaccine without the limitations of the conventional live vaccines. It is the reason why Ceva, a leader in poultry vaccines, has developed a new approach to LT vaccination with a vectored vaccine: Vectormune FP-LT. 9 O. Langlois Latent and persistent LT virus infection = chronic carrier state in vaccinated birds Reversion to virulence Transmission to other birds Shed into the environment Induce vaccine reactions that affect growth performance The avian encephalomyelitis (AE) virus, Calnek strain has been added to the vaccine in order to get protection for fowl pox, LT and AE. 9 O. Langlois These vaccines are able to provide protection but conversely, they have many side effects (Bagust 1986 and 1995, Graham ):

Duration of LT immunity 5 Vectormune FP-LT vaccine strain does not spread from vaccinated to non-vaccinated birds Vaccination of 8 week old SPF chickens with Vectormune FP-LT or with the Fowl Pox parent vaccine strain by wing web method was performed. Susceptible contact birds were placed in each isolator 24 h post vaccination. A group of SPF birds were not vaccinated and used as control group. A challenge was done with a fowl pox virus 3 weeks post-vaccination. Chickens were observed daily for days post challenge. 8 weeks old SPF birds were vaccinated via wing web with. A non-vaccinated group of birds remained as control group. A total vaccinated chickens per age group were challenged at, 24 and 32 weeks, with LTV USDA challenge strain via infraorbital sinus route. The non-vaccinated group composed of 15 birds were challenged at the same ages. Fowl pox protection to evaluate virus spreading capacity Infectious laryngotracheitis protection % FP protection Vectormune FP-LT Vectormune contact birds 9 Parent FP contact birds / Significant statistical difference between vaccinated and control groups are shown by different signs, p <.5 using the Fisher exact test. There was no statistical difference on protection among the vaccinated groups at different ages. 9 O. Langlois Group The susceptible chickens, in contact with the Vectormune FP-LT and Parent FP vaccinated chickens, were not protected against FP challenge. Vectormune FP-LT vaccine strain does not spread from vaccinated birds to non-vaccinated birds. 6 Protection with VECTORMUNE FP-LT & Comparison of Vectormune FP-LT + AE with live LT CEO and TCO vaccines A total of four groups of SPF chickens 8 weeks old were vaccinated as follows: Group 1: by wing web - Group 2: Live LT CEO vaccine by eye drop Group 3: Live LT TCO vaccine by eye drop - Group 4: Negative controls The chickens were challenged at 3 weeks post-vaccination with an LT virulent reference strain from the USDA, challenge via infraorbital sinus route. The birds were observed daily for clinical signs of LT during days after challenge. Infectious laryngotracheitis protection comparison 9 Parent FP strain CEO vaccine 9 TCO vaccine no significant statistical difference among challenged groups, at p <.5. Group All three vaccines were efficacious. Vectormune FP-LT vaccinated chickens were as protected as the chickens vaccinated with the live LTV CEO or TCO vaccines. 9 O. Langlois weeks 24 weeks 32 weeks The challenged birds were protected after LT virus challenge at, 24 and 32 weeks of age compared to non vaccinated and challenged control birds.

Fowl pox protection 8 weeks old SPF birds were vaccinated via wing web with. A non-vaccinated group of birds remained as control group. A total birds vaccinated chickens per age group were challenged at, 24 and 32 weeks, with FP USDA challenge strain via wing web route. The non-vaccinated group composed of birds were challenged at the same ages. 7 Monitoring Vaccine Take Vectormune FP-LT does not spread from vaccinated to non-vaccinated chickens. The vaccine should be carefully applied to each bird in order to reach complete flock protection. The vaccine should be applied to the wing web with the double pronged applicator delivered with the blue diluent and the vaccine. Fowl Pox protection 9 / Significant statistical difference at p <.5 by Fisher exact test between vaccinated and control group weeks 24 weeks Application should be done to the bottom part of the wing in order to avoid the risk of losing vaccine in the feathers present on the upper part of the wing. 32 weeks challenged birds were protected after fowl pox virus challenge at, 24 and 32 weeks of age compared to non-vaccinated and challenged control birds. Avian encephalomyelitis protection A total of 31 SPF birds of 8 weeks of age were vaccinated with via wing web route. A total of SPF birds remained as control group. The birds were challenged 3 weeks post-vaccination with an USDA AE challenge virus strain intracerebrally. The birds were daily monitored for AE signs during 5 weeks post-challenge. You can also use a wing web syringe. You should insure that the syringe is delivering the right dosage of vaccine :.1 ml per bird. Pay particular attention to ensure needles are projected from the syringe only after the syringe body is touching the birds skin. Otherwise there is a risk that the projected needles will deliver a portion of the vaccine in the feathers of the birds. Take care to maintain the syringe in a vertical position (needles pointing down) to ensure the correct quantity of vaccine is delivered. Monitoring of vaccine take should be done between 5 and 8 days post-vaccination at the wing web injection site by evaluation of skin swelling due to fowl pox replication. Immunity to LTV in chickens is determined primarily by a cell-mediated response mechanism of the immune system (Fahey and York, 199). Therefore, serological monitoring of vaccinated birds with an Elisa test is not recommended. Vectormune FP-LT does not induce detectable LT serological response. Avian encephalomyelitis protection 9 References Bagust TJ. Laryngotracheitis (gallid-1) herpesvirus infection in the chicken 4. Latency establishment by wild and vaccine strains of ILT virus. Avian Pathology, 15:3, 581-595.1986. Bagust TJ., Johnson MA. Avian infectious larynogotracheitis : virus host interactions in relation to prospects for eradication. 11 weeks 9 O. Langlois Avian Pathology, 24:3, 373-391.1995. Fahey KJ and York JJ. The role of mucosal antibody in immunity to infectious laryngotracheitis virus in chickens. J Gen Virol. 71 : 21-25.199. Graham DA., Mc Laren IE., Calvert V., Torrens D., and Meehan BM. RFLP analysis of recent Northern Ireland isolates of infectious Vectormune FP-LT + AE challenged birds were protected after AE virulent challenge at 11 weeks of age. laryngotracheitis virus : comparison with vaccine virus and field isolates from England, Scotland and the Republic of Ireland. Avian Pathology, 29, 57-62..

8 Vaccination schedule From 1 week of age 4 weeks before production Rearing period Production period From 8 week of age 4 weeks before production Rearing period Production period No Fowl pox vaccination should be done prior vaccination with Vectormune FP-LT or Vectormune FP-LT + AE No field fowl pox exposure should occur prior vaccination with Vectormune FP-LT or Vectormune FP-LT + AE Precautions: No vaccination with Vectormune FP-LT or Vectormune FP-LT + AE during lay. Withdrawal period: 21 days Labor saving administration Features and benefits Vectormune FP-LT Vectormune FP-LT and Vectormune FP-LT + AE eliminate the need for eye drop administration of LT live vaccines, reducing labour cost associated with handling the birds. Safety Vectormune FP-LT and Vectormune FP-LT + AE do not induce any post-vaccinal reaction due to LTV live vaccination in vaccinated chickens. Vectormune FP-LT vaccine does not spread from vaccinated birds to non-vaccinated birds. Effective Vectormune FP-LT and Vectormune FP-LT + AE induce strong immunity against ILT, fowl pox and encephalomyelitis in a single wing web application. Summary Product Characteristic Composition: Vectormune FP-LT contains a live freeze dried fowl pox recombinant vaccine indicated for use in chickens. The fowl pox virus in Vectormune FP-LT expresses key protective infectious laryngotracheitis virus antigens. Indications: Vectormune FP-LT is indicated as an aid in the prevention of fowl pox and infectious laryngotracheitis in chickens. Vaccinate chickens 1 week of age or older, but at least 4 weeks prior to the onset of production. Administration: Reconstitute the vaccine with the sterile diluent delivered with the vaccine. Inject.1ml per bird by wing web. Special precautions for use: Vaccinate healthy susceptible birds only. Vectormune FP-LT must be the first fowl pox vaccine administered to the chickens. Prior infection of the chickens with field fowl pox virus will interfere with protection of the vaccine. Withdrawal period: 21 days. Storage: Keep it cool between + 2 to + 7 C (34 to 45 F). Composition: Vectormune FP-LT contains a live freeze dried fowl pox recombinant vaccine associated to a live Calnek avian encephalomyelitis virus strain. This vaccine is indicated for use in chickens. The fowl pox virus in Vectormune FP-LT expresses key protective infectious laryngotracheitis virus antigens. Indications: Vectormune FP-LT + AE is indicated as an aid in the prevention of fowl pox, infectious laryngotracheitis and avian encephalomyelitis in chickens. Vaccinate chickens 8 weeks of age or older, but at least 4 weeks prior to the onset of production. Administration: Reconstitute the vaccine with the sterile diluent delivered with the vaccine. Inject.1ml per bird by wing web. Special precautions for use: Do not use during lay. Vaccinate healthy susceptible birds only. Vectormune FP-LT + AE must be the first fowl pox vaccine administered to the chickens. Prior infection of the chickens with field fowl pox virus will interfere with protection of the vaccine. Withdrawal period: 21 days. Storage: Keep it cool between + 2 to + 7 C (34 to 45 F). CEVA SANTE ANIMALE, Avenue de la Ballastière - BP 126-33 LIBOURNE Cedex (France) Tel : + 33 5 57 55 - Fax : + 33 5 57 55 41 92 - www.ceva.com RC B 3 289 5