anti viruses are good but they won't always protect you against everything. you still have to be careful yourself, don't download any random things you don't trust, don't visit shady links,... and obviously you must use cold storage. hardware wallets are good but that is not the only option. for "storage" you can always use a paper wallet that costs practically nothing.
Anyone that is serious about the protection of his coins needs to really think about changing its operating system to something way more secure than windows, I know that Linux can be more inconvenient when it comes to certain software and specifically when it comes to games but that should not be a factor when we consider how secure our coins become by using Linux, if you choose to use Linux this makes the issue of the antivirus moot and your coins will be many times more secure.