Dozens of orchids dying to a strange fungus? PICS

[imationkarl]

Hello!

I work at a Gardening Supply. We've had good luck with previous orchid orders, but nearly every plant in the last order came with a strange fungus. The leaves start by wilting and turning yellow, from the bottom of the plant up. Eventually, a strange round pattern develops encircled by another round pattern. Very strange. Any advice on diagnosis and treatment?

Hope the pic worked.

Thank you so much,
Karl