Most malware are written for Windows because of its market share, however irrespective of OS platform (Windows or Linux or Android or …), you need a good anti-malware application against viruses, worms, adware and other malware.
ClamAV is free and open source Anti-Virus, also available for Linux.
To install ClamAV, open terminal and use below command line:
$ sudo apt-get install clamav clamtk
Once installed, you can access ClamAV from dashboard:
You may set some useful preferences:
To update virus definitions, type:
$ sudo freshclam