If an Avast Evangelist is assisting you, who usually refers you to a malware specialist based on information you give them and the logs you attach, then yes it is safe. Sometimes, people mean well who are newbies or trolls and don't know what they are doing. However, some new people who are not Evangelists but are advanced users have a lot to offer; in cases like this, usually an Evang. will jump in the thread and have a comment to make.
You will see next to their name, like mine, Evangelist or by the number of stars. So if they suggest that you attach a log for malware removal, there is a good reason for it, and we are doing it in preparation for the malware removal specialist to speed things up for you in removing your malware.
Running a scan will not harm your machine, especially the ones suggested in the Worms and Virus section. I would be more worried leaving the malware on your machine. Let us know if you have any further questions. Thank you.
