Disease spreads alarm, disheartening India (7)
I believe the answer is:
malaria
'disease' is the definition.
(malaria is a kind of disease)
'spreads alarm disheartening india' is the wordplay.
'spreads' is an anagram indicator (I've seen 'spreading' mean this).
'disheartening' means to remove the middle letters.
'india' with its middle removed is 'ia'.
'alarm' with letters rearranged gives 'malar'.
'malar'+'ia'='MALARIA'
(Other definitions for malaria that I've seen before include "Disease from bites by infected mosquitoes" , "Fever disease transmitted by mosquitoes" , "Mosquito-transmitted disease" , "Protozoal disease" , "Mosquito-borne disease" .)