Other virus infections can trigger AI

07-12-2006 | |

Research presented at the EAGLES Symposium in China this week indicates that avian influenza occasionally occurs in vaccinated poultry because of co-infection with other immunosuppressive viruses.

Professor Zhizhong Cui from Shandong Agricultural University presented data which showed that sporadic outbreaks of avian flu could coincide with outbreaks of other immunosuppressive viruses.
These findings were supported by experimental data showing that several immune suppressive viruses have the ability to weaken the immune protection in vaccinated chickens. With a weakened immune defence, the chickens are vulnerable to avian flu virus.
This information indicates that current vaccination programmes alone cannot guarantee control of avian influenza in commercially farmed chickens, because various immune suppressive viruses are widespread in chicken farms and have the ability to make the chicken vulnerable to avian flu even after vaccination.
The professor commented that the prevalence of immunosuppressive virus infection in chickens is not well known and should be studied in more detail. There may be a need for a new vaccination strategy targeting a range of viruses in order to control avian flu, he said.