Apart from using anti-virus software, there are some simple steps you can take to protect your laptop from viruses. Not opening suspicious emails especially those in the spam folder is one of these. You should also use longtail and constantly changing passwords and not clicking on links for free software from third parties but go to the actual sites to acquire the software among others. It might sound funny but I mostly use my sixth sense to evade viruses reinforced by years of prescence on the web.