'pathogen-borne' is a compound of 'pathogen' and 'borne'. 'Pathogen' ultimately comes from Greek elements (via New Latin/Modern scientific English): 'patho-' from Greek 'pathos' meaning 'suffering' or 'disease', and '-gen' from Greek 'gennan'/'genēs' meaning 'producing' or 'origin'. 'Borne' is the past participle form of English 'bear', from Old English 'beran' meaning 'to carry'.

'pathogen' was formed in modern scientific usage (New Latin/Greek-root formation) to mean a disease-causing organism; 'borne' is historically from Old English 'boren' (past participle of 'beran'). The compound 'pathogen-borne' developed in modern English scientific and medical contexts as a descriptive compound (pathogen + borne) to indicate something carried by pathogens.

The element 'borne' originally meant simply 'carried' or 'carried by'; combined with 'pathogen' it has come to mean specifically 'carried or transmitted by disease-causing organisms' in medical contexts.