RuneScape lag? Please help!?

I am now lagging in bursts for RuneScape. Every 7-8 seconds, I will lag for about 2. It gets annoying, and I have nothing else open but RuneScape! And no, I don't have a sucky computer, because I have been running RuneScape and World of WarCraft for years! Now it's lagging all of a sudden. I ran a virus scan and removed 4 threats. That stopped the lag. Then I ran another one but it was an incomplete scan. When I go to Task Manager, I have 55 processes open and my CPU Usage rangers from 79%-98%. Help!