Fusarium Wilt

[Sharon's Sheepdogs]

I really could use some help with this. Several weeks ago, I found one of my orchids was suffering from Fusarium Wilt. I could identify the disease because of the purple colored ring I found when I cut into the rhizome. I'm aware the fungus is very contagious.

My question is whether finding pink tissue in the orchid rhizome or pseudobulb before the purple ring actually develops is an early symptom of fusarium. Sometimes when I'm cutting a a backbulb off while cleaning up a plant to repot, as I cut into the rhizome I will find small pink nodules in the tissue but no pink coloring elsewhere. The nodules are hard & difficult to cut out. Could this be another early sign of fusarium?

Are there times when finding pink tissue inside the rhizome or pink, reddish coloring on the outside such as the bands along the pseudobulbs is normal or are these possibly early signs of fusarium also?

I know this is a fungus you want to catch early to attempt to stop it. I'm trying to figure out how the earliest symptoms manifest themselves so I can detect & treat the disease sooner than later.

Thanks for any help you can provide.