Insects caught disease (8)
I believe the answer is:
crickets
'insects' is the definition.
(cricket is a type of insect)
'caught disease' is the wordplay.
I cannot really understand how this works, but
'caught' could be 'c' (cricket abbreviation) and 'c' is found within the answer.
'disease' could be 'rickets' (rickets is a kind of health problem) and 'rickets' is found in the answer.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for crickets that I've seen before include "Chirping insects" , "Noisy insects" , "They are chirpy" , "Insects that chirp in chimneys" .)