H7N9 influenza vaccine failure may be due to immune camouflage, study reveals

The avian influenza A (H7N9) virus has been a major concern since the first outbreak in China in 2013. Due to its high rate of lethality and pandemic potential, H7N9 vaccine development has become a priority for public health officials. However, candidate vaccines have failed to elicit the strong immune responses necessary to protect from infection. A study published in Human Vaccines & Immunotherapeutics has revealed that it may be due to immune camouflage.

https://www.news-medical.net/news/20150925/H7N9-influenza-vaccine-failure-may-be-due-to-immune-camouflage-study-reveals.aspx

Thank you so much my dear Syed Amer Gilani for your scientific answer , hope you always healthy and successful in your work and in your general life ,, Best regards ,, Jawad Ali

Perhaps due to variance of the antigenicity

I am guess so ,, thank you dear dr. Ishag Adam for your answer,, wish for more successful in the new year ,, Best regards ,,,Jawad Ali

Thank you dear dr. Argya Mani for your answer ,, happy new year ,, Best regards ,, Jawad Ali

Dear Jawad Ali,

I understand that you are asking about vaccination of poultry, not humans, so I will answer accordingly.

What do you mean with "active"? If you mean live vaccine, then it is very risky to use live mild viruses for vaccination of poultry since such viruses can mutate in poultry into highly pathogenic viruses (H5 and H7 subtypes) and they can also re-assort with filed viruses giving new field strains with unpredictable features.

The only solution is use of either inactivated or vectored vaccines for vaccination of poultry against avian influenza. Such vaccines can be effective given that the antigenic composition between locally circulating field strain and used vaccinal strain match. The downside of efficient poultry vaccination is that vaccinated poultry will harbour, multiply and excrete field virus although not showing any signs (Trojan horse). Further, serological monitoring of infection is extremely impeded (you can read about DIVA approach - Article DIVA Vaccination Strategies for Avian Influenza Virus

That is why many authorities do not want to vaccinate poultry against influenza except in situations where there is no other option.

Thank you dear dr.Vladimir for your scientific answer really hope for you more successful in your scientific and general life .. Best regards ,, Jawad Ali

It is agood question.

greeting

thank you dr. Khalid for your comment ,,, Best regards ,, Jawad Ali