Ignite

Hello there! Lately I have been maining swain, olaf and mundo but im encountering a problem. Ignite. How do I stop it? the 50% healing reduction is a royal pain, how can I play around it? In bronze I could bait it easy, some times you would get ignited at 50% hp in bronze. But im finding people are more productive with it. Does cleanse remove the 50% healing debuff? Is there anything I should build to counter it?

My current olaf build is

Is does vary. Any tips? Its more of a problem on that first duel. Its always holding me back to go full in.