No, never have in over 22 years, and I spend hours on the internet almost daily.

The one time I used an anti-virus program on a Mac (corporate initiative), guess where the virus was?

I use the free version of Malwarebites, which doesn’t provide real-time protection (hence doesn’t steal CPU cycles). But I run a Malwarebites scan (takes ~25s) before each TimeMachine backup, so I know my backups are clean. Malwarebites has never reported anything other than “Congratulations, you are clean”.

ClamXAV works fine. Used to be free, now it's shareware. It's caught some things.

The most annoying thing now are websites than claim your Flash player is out of date and needs an update. If you fall for it, you will probably install a trojan horse. I always check the Flash control panel and see if I need an update and it usually says "up to date".

For Macs all u need is regualr security updates

For Windows all you need is Windows defender and regular updates

Avast and all the other Vrus protection scams are garbage and you are fooling yourself by using them. They create more vulnerabilities and by the time they "Find something" its to late. Also these programs start hogging your CPu resources.

All garbage

none. nada. zilch.

The gentleman that turned me on to Macs 10 years ago just looked at me funny, in that way only a good friend can without asking about your intelligence when I asked about antivirus, spyware, etc.

I just smiled and have been smiling ever since.