@Shilolo, where do you practice? Perhaps chiggers is a regional colloquialism.
Growing up in the Grand Ole South, we referred to the “tiny red bugs” simply as “red bugs”. They were different than “chiggers” which were typically dark brown/black in color (and I have no idea if those were some sort of mite), but they were practically as small.
Point is, south of the Mason-Dixon, you might want to recalibrate your diagnostic vocabulary to include “chiggers” as a local species, not foreign exotic.