Affiliate Marketing Secrets

I don’t know what has caused this, is it a virus? (I’ve done a scan and there was a trojan horse, but it deleted it)
For example, I’ll click on PC World, and this will come up: http://itcg.20446_1265.get-search-results.com/jump2/?affiliate=itcg&subid=20446_1265&terms=pc%20world
So far, it has also done the same for the BBC website, but not every time.