Ear Fungus is a human medical condition that may be associated with flu-like symptoms and can be spot-diagnosed by shining a bright blue light into the ear canal. It is possible that it is in some way related to the presence or non-presence of N.B.E.s on Earth. Or maybe it isn't.
Class 2 Ear Fungus is a particularly virulent strain. It is recommended that physical (and especially ear-to-ear) contact with contaminated individuals be avoided.