Dear Jalil,

Please refer to the links below and attached file for the requested information.

Best wishes

SM Najim

http://www.oie.int/fileadmin/Home/eng/Health_standards/aahm/current/chapitre_viral_encephalopathy_retinopathy.pdf

http://www.jifro.ir/article-1-1436-en.pdf

Dear Dr. Salah,

Thanks for your kindly message and valued Data especially VNN  Protocol of VNN that could be our main guidance for isolation and confirmation of VNN virus.

Meanwhile,  the second article would be belong to our Ph. D candidate  (Dr. Alireza Nazari) that discussed about main location of target section of VNN  virus in the affected fish brain as follows:

In the brain, vacuoles were seen in the stratum griseum ventricular layer and stratum album central layer of mesencephalon region, as well as in the septal area, ventral and dorsal olfactory area in olfactory bulb of telencephalon region.

Meanwhile, What about occurrence of VNN in your country, Iraq?

Dear Jalil,

Since fish diseases is beyond my field of specialization, I put your request about VNN in Iraqi fishes into a question for colleagues. Please follow it on the link below.

Best wishes

SM Najim

https://www.researchgate.net/post/Viral_Nervous_Necrosis_VNN_disease_in_fishes_of_Iraq

Dear Jalal

You can direct your question to colleagues competence of diseases and parasites Fish

sadiq jawad muhammed

 The diseases caused by these viruses are commonly known as viral nervous necrosis (VNN) or viral encephalopathy and retinopathy (VER). These viruses damage the central nervous system in susceptible fish species and typically affect younger stages of fish (larvae, fry, fingerlings), although older, market-size fish can be affected as well, with losses ranging from 15–100%.

Khalidah s AlNiaeem

Dear Dr. Khalidah,

Thank you for your response.

What about VNN disease in your country?

Did you have an official report of the occurrence of VNN in your marine fish in Iraq?

Dear Dr. Jalil,

The disease had not been recorded in Iraqi marine fish, and I follow both cases that occur in Iraq.

Best wishes

Khalidah S AlNiaeem

Dear Dr. Khalidah,

Thanks again for your valued response.

Please follow up Dr. Azad Article that was reported VNN from Kuwait about 3 years ago.

Kindly regards

Jalil

Dear Dr. Zorrieh

I read that virus could be found in brain , in spinal column and even in peripheral ganglions.  Subspherical viral particles, about 25

nm in diameter, can be visualised in

brain, spinal cord and retina of

heavily infected animals. The virions may appear ei

ther free in the cytoplasm or associated to the

endoplasmic reticulum membranes, primarily in nerve

cells astrocytes, oligodendrocytes, and microgliocytes.

I try to ask our friend also and send you the more information.

Regards

Sinaki

Dear Dr. Sinaki and all of my dear respected friends,

Thanks a lot for your kind attention and valued investigation about mentioned question. According to my knowledge, target location of virus attack could be one of important indicator for rapid diagnosis and then control and prevention of next outbreak in sensitive populations. 

Also, as you know VNN could be one of neurotropic Virus that having an affinity for or localizing selectively in nerve tissue.

Maybe, it similar to Rabies virus in the human which from the point of entry, the virus is neurotropic, traveling quickly along the neural pathways into the central nervous system (CNS) in human.

Your valued feedback would be appreciated.

Kindly regards