be bitten by a bug potocznie , także: get bitten by a bug
be bitten by the activity bug

"She has been bitten by a bug and has a passion in her belly about doing documentaries."

Then I was bitten by a bug and here I sit, nearly two months later wondering what hit me.

The Green Ripper "She told me she was bitten by a bug this morning.

Bu Starkweather had been bitten by a bug, and he had infected Trencrom, too.