I know it's an old issue regarding worm-Kido.ih

Client have 200 Workstations & 10 Servers, signatures are up to date on all PCs

What is the best way to delete kido, since each time it is deleted it comes back again and it freezes their business.

I've performed full scan for all the network with high level of security but it still back.

Please Advise me

Hi
Did you perform windows update/pactches to all your machines?
Try to delete deleted viruses on local machine then try to perform full scan, if the issue still the same try one machne boot in safe mode and perofrm full scan.
Thanks

I've already installed all of Microsoft patches.

It's not logical to perform full scan on that huge number of PCs on the Safe Mode!! it may take weeks..

Is it useful to delete the viruses from the local machine!!?

Read this article.

I've already read it, in fact i need something Practical not Theoretical.

You did not read it......at the end of the theory you have a nice link that will forward you to a page full of guidelines and tools to fix it up....
M