AVG 9.0 Virus search?

I just downloaded the AVG 9.0 trial (30 Days) and seached for viruses and It found like 100 or so and healer removed or moved them to vault Im wondering to know if those viruses can harm me if the AVG goes out of date or removed couse it seemed to be that program(avg) keepin them in some place so they could not harm your computer and if the program doesnt exist the viruses will be released? or they are just removed or becam harmless I dont know much about virus programs :/ help please.