Yes, it's possible, any device with sufficient storage is a potential hiding place. However, I'd call this an academic discussion at best because it would challenge some of the best programmers out there to create such a beast and given the variations on hardware from computer to computer it wouldn't necessarily be possible to create or maintain the secondary infection on every computer. The only people who'd be interested in doing such a thing would be governments and maybe the odd really bored genius type who's probably one in a million.
What is far more likely to happen is a virus/worm spreads to another computer, so even after you replace the HDD on the first computer, once you reconnect it to the same network as the second computer, it becomes infected all over again. People today are far more interested in making money off of you than writing destructive viruses, plus the number of people with the skill to write a destructive virus has nose dived. Most so-called hackers today are all using one or two programs that almost completely automate the process of probing a system for known vulnerabilities and delivering a payload if one is found. Take that program away and these people are probably even more clueless than the average person about computers.
when the hard disk of a laptop is replaced by a new one is that possible the viruses in memory or in some other hiding place
be still active?