The best anti virus still is our self awareness. Sorry for your loss OP. This is the reason that even we've got self awareness with our browsing activities, it's always best to check receiver's address carefully before doing a transaction.
This why I always advice to use mobile for transaction and stay away from doing any single transaction in the PC where this scam attacks are in the high numbers.
It's opposite for me, it's still best to check transactions through a PC or laptop setup. Or, when you have spare devices, you can be meticulous and just use it specifically for transactions and you won't do any browsing there or any downloads aside from the wallets that you have there.