
The U.S. Department of Homeland Security has [url=https://www.dhs.gov/ynews/releases/pr_1238443907751.shtm]posted some guidelines[/url].
On that page they list various tools to help identify and remove any infections your PC may have. [url=https://www.symantec.com/business/security_response/writeup.jsp?docid=2009-011316-0247-99]Here is a tool by Symantec[/url] that you can download for free.
You can also download the [url=https://www.microsoft.com/security/malwareremove/default.mspx]Microsoft Malicious Software Removal Tool[/url]. Although there should be one already running in the background, it may make you feel good (it did for me

If you are unsure of your own antivirus software or want to supplement what you have, I recommend [url=https://download.cnet.com/Malwarebytes-Anti-Malware/3000-8022_4-10804572.html]a FREE program called Malwarebytes[/url]. This program doesn't continuously scan your computer (you have to pay for the full version for that), but if you already have an antivirus software you may want to download this one to make sure all the viruses, trojans, and malware are completely off. I caught some trojans with Malwarebytes that others missed. It's highly recommended by the staff at CNET.com. I like it because it doesn't slow down my computer and catches things the other programs miss.