Cowardly fellow, always bringing complaint (6,5)

I believe the answer is:

yellow fever

'complaint' is the definition.
(yellow fever is a kind of disease)

'cowardly fellow always' is the wordplay.
'cowardly' becomes 'yellow' (yellow can informally mean cowardly).
'fellow' becomes 'f' (abbreviation - of a society etc.).
'always' becomes 'ever' (synonyms).
'yellow'+'f'+'ever'='YELLOW FEVER'

'bringing' acts as a link.

I've seen this clue in The Daily Express.

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