Oh this is terrible news! This is the kind of thing that makes non-native species so dangerous...the junk they bring with them that also doesn't 'belong'.
I hereby invite all the pygmy rattlers to come to my "safe" house...
IIRC one of the hurricanes that hit Florida - Andrew? - clobbered an import facility and that's the source of a lot of the Florida burms. Many importers don't treat for internal parasites. So, it would make sense that any burms released before being sold and treated would have unfortunately spread any parasites they were carrying at the time.