Stop malware from being executed by launchd
There is an app Malwarebytes which is popular for detecting and deleting Malware. I don't know how this compares to Nortons but maybe its a viable option. The website,located here https://www.malwarebytes.com/mwb-download/,  advertises a free version.  The full application is available here: https://www.malwarebytes.com and also offeres a free version.