Literally meaning: “diagnosis through a foreigner”
Origin: Anc Greek
+ δια-/dia-(through) > δυο/dio(two)
+ γνώσις/gnosis(=(inquiry, knowing) > γιγνώσκω/gignosko(=come to know, to learn). To the Greeks a diagnosis meant specifically a "discrimination, a distinguishing between two possibilities more compatible with differential diagnosis.
Xenodiagnosis is the diagnosis of an infectious disease by exposing an infected individual or tissue to a clean vector and then examining the vector for the presence of the infective microorganism.