Introduction The avian influenza virus (AIV) H9N2 subtype was first characterized in 1966 as causing mild respiratory diseases in turkeys (Homme and Easterday, 1970) and, for the first decade after its isolation, was found only in shorebirds and mallards (Kawaoka, et al., 1988). However, after almost 50-years evolution and propagation, the H9N2 viruses have spread across most of the ea...
Dear Eng. Ehab ,
Thank you for your comments for sure your support and long experience in the poultry industry will add big value to help our customers.
What are the characteristic of the H9N2 that is used in the vaccine. Where and when was the virus isolated ND to which genetic flair it belongs? Thanks.
The H5N8 is moving around Europe, they found as well in Israel. What connection will have with the H9N2? Can the birds effectively carried different strain and what makes it more prevalence in the population?
H9N2 strains are endemic in the Middle East with new claids developing every 3-4 years. The new H5N8 introduction to the region is very new and not sure we can predict any interactions between the two.
Dear Avner, Thank you for your comments and your question. The one used in the vaccine is the same one that has been isolated from the area 1998 which most of the vaccines companies are using. The difference in response to the vaccine are: 1- vaccine application. 2- Type of the adjuvants used . 3- Time of vaccination. Last 2 years we have reisolated the virus again and we found it still the same one in the vaccine. The above points were playing big role not to get the right immunity from the vaccine and also other diseases like ND or IB were playing a role making the losses more than expecting . That why to control AI very well you should look to other diseases to be also control. We are lucky we do not have H5 in our area since long time and hope we will not, but you never guarantee, as you know, diseases do not need visa to get in.
Dear Dr Husam Bakri
I am looking for a job and working with you on AI and ND. Please may you let me know your email to send you my CV. I am virologist with research interests in AI and ND
You gave an example of vaccination of laying hens that is broiler chickens who have the vaccine on day 1 with that dose is that there is no interaction with the AOM of maternal origin and the immunity settles after how long.
Which it is the title elisa after vaccination with Nobilis H9 Thank you.
Such study should be done in the African countries. But unfortunately due to lack of finance and resources, this has not been done in a large scale. It is with great concern to know that in IRAN, the virus H5N8 is responsible for the death of 5 583 birds and 277 878 birds have been destroyed. A big blow to the poultry industry in Iran.
Dear Mohsen, Thank you for your comment. We are advising to be vaccinated at day one in the hatchery for the following reasons: 1- Easy to control the vaccination and to be sure that birds got the vaccine right. 2- We need to avoid giving the vaccine in the farm to keep biosecurity good, as you know in some countries vaccination team moving from farm to farm without taking care biosecurity.
Please be sure that you will take care of other diseases which they are also challenging the poultry farms like ND or IB virulant strains .
Dear Dr. Narendra ,
Thank you for your support . Trust without your support these study will not be usfull for our poultry industry .
You have done a lot to make these happened .
Thank you again for every body support these activities to help our farmers .
One hand can not clamp for sure .
Dear Dr. Douayad ,
Thank you for your email. From our experience MDA is play very good role to protect the broiler at early age, from our experience we did not see any negative feed back from using AI vaccine at day old with MDA.
We are using HI test not elisa test.
All the best
Mexican experience indeed indicates that MDA play an important role in seroconversión of vaccinated birds, specially if intended to be vaccinated at day old. This is the reason they have to be vaccinated in the farm between 10-14 days in current vaccination programs. Vaccinated at day of age gives por seroconversión and protection if MDA are high.
I agree with Dr Decanini
Vaccination of broilers with maternal antibodies is not effective. Birds with MDA should be vaccinated when titre decrease to HI 3-4, otherwise the vaccine will not penetrate.
I found it strange that a strain from 1998 is still protective. in all the work done in Israel it was clearly demonstrated that the 2001 isolate used in the first H9 vaccine had to be replaced after 4 years. data was presented in last WPVA congress in RSA
Avner
I agree with Dr. Avner Figner, updating of the vaccine strain si very important in terms of protection, specially in killed vaccines. In Mexico this is done once a year.
Dear Eduardo,
Thank you for your comment. I am sure you are talking about H5 strain as far I know you do not have H9 . As you know H9 has been found long time ago and so far still same first isolation , yes it may has some changing but it did not come like H5 which you need to be sure that vaccine strain it match with the new field isolation.
As I mentioned we have reisolated the stain from 3 countries in the regain and we have found that the vaccine strain still doing well against the filed strain , but the issue here we do have more diseases come with it like ND or IB that why we see the damages more , this lead to think that the starin has been changed .
Most of the farms are using the vaccine with excellent results. The only point here I would like to fouce on it that when you have early challenge from AI H9 in the broiler first 2 weeks yes the vaccine will not help not because strain has changed , it is coz vaccine did not work in these age as it is Killed vaccine.
All the best to all my Frind in Mexico
