Mariana,

Don't weep, girl! Down here in FL the ugly worms are common, but I rarely
have seen them around my plants. Only twice, when repotting from old bark
(these were plants I acquired in bark; I prefer not to use it, myself).
While the roots were bare I sprayed the plants with alcohol and soap, and
never saw them around the pots again.

You mention that you grow in several locations around the house. If the
beasts were found only in one location, maybe repotting the ones near it
would be enough.

For me, growing outside, if it were a big problem I'd look for a systemic
labeled for the critters, but inside - golly. I think I'd be on the phone to
the nearest orchid nursery and/or the county Ag station.

GL

Diana