Become septic after gathering in hospital department (6)
I believe the answer is:
fester
This could be a double definition.
'become septic' is the first definition.
(I've seen this before)
'gathering in hospital department' is the second definition.
'fester' can be an answer for 'gathering' (thesaurus). I am not certain of the 'in hospital department' bit.
'after' is the link.
Can you help me to learn more?
(Other definitions for fester that I've seen before include "strange uncle" , "Putrefy" , "Rankle" , "Of wound, become septic and filled with pus" , "Suppurate" .)