"He has a virus."
Translation:Tá víreas air.
'Ar' (orm, ort, air etc) meaning 'on' is used for illnesses and emotions. Also hunger/thirst.
Tá ocras orm (lit - hunger is on me) Tá tinneas ort (lit - sickness is on you) Tá brón air (lit - sadness is on him)
'Aige' does not mean he has but rather 'at him'.
There is no verb 'to have' in Irish so the functions of having something don't translate to a single word. The translation of 'a virus is on him' is not correct in English so the nearest and most natural equivalent in English is given, ie 'He has a virus'.
Ag (agam, agat, aige etc..) are used for physical possessions - you don't own the virus. Illnessess were probably viewed more abstractly in the past. People couldn't see the virus only the symptoms.
A virus is something that 'comes over' or 'on' you in a sense.
The NEID uses air rather than aige for this exact sentence. Ar rather than ag is also used for other medical conditions, e.g.
- he has the flu tá an fliú air, tá an ulpóg air
- he has chicken pox tá deilgneach air
- he has measles tá an bhruitíneach air
Ag seems to be preferred for organs, e.g.