You might send a message to people who you believe have you in their address book and explain that you are receiving these strange messages, that you believe they may be coming from someone's computer without the owner's knowledge, due to a virus in their computer, and ask them to install an anti-virus program if they do not have one installed.
Other than that, I don't believe there is much you can do other than, as you said, change your email address. And, that might only be a temporary solution since you do not know exactly whose computer may be generating these messages and future email exchange with them could result in your new address getting retained in their system and in a resumption of these unwanted messages.
If these messages contain some common element that could be used in a message "rule" or "filter", you could create a rule or filter that sends these messages directly to the trash folder.