Yes, I'm suggesting it is a fungus or bacteria (er-"bad" bacteria) possibly. Tea tree oil will kill it off likely.
If there is fungus / bacteria the tea tree oil (an essential oil) will likely feel like a burning sensation. If there is no fungus or bacteria it won't burn it'll feel fresh and tingly.
I'll have to post about the enzyme angle tomorrow, as my little one needs to nurse. Stay tuned. :>