Serological Monitoring of Turkey Flocks After Using Avian Influenza H5 Vaccine in Iran

 Avian Influenza (AI), an acute infectious disease of waterfowl, poultry, animals, and wild birds, is transmitted zoonotically to humans. There are some reports on the HPAI incidents in Iran: H5N8 and H5N1. The Iranian Veterinary Organization decided to vaccinate turkey flocks after the outbreak in high-risk provinces in Iran. The present work aimed to evaluate the vaccine’s serum response in turkey flocks in the provinces of high risks.

 From Tehran (no:1), Isfahan (no: 3), Zanjan (no: 1), and Mazandaran (no:1) provinces, six broiler turkey farms were chosen and received the H5 vaccine (two times of vaccination for each farm). From each flock, 15 blood samples were taken. The HI test was conducted using 4 HA units of the homologous antigen and a U-bottomed microtiter plate.

 The antibody mean titers in the turkey farms previously receiving the vaccine were 1.23. However, they were 5.05 for those receiving the immunization twice (significant difference; p<0.05). Moreover, considering protection baseline 4, all flocks produced higher titer by injection of the vaccine twice.

 Integrating with other control measures like good monitoring and biosecurity programs, vaccination is an appropriate and robust instrument for supporting control programs or AI eradication in endemically infected countries. The regular post-vaccination surveillance was performed by the Iranian Veterinary Organization (IVO), and the flocks were evaluated for silent infections.