### Clue: Serious complaint originally brought up by our corporal in New Guinea (7,6)
### Answer: BUBONIC PLAGUE 
 ### Explanation: Definition: Serious complaint

[*originally*] **B**(rought) **U**(p) **B**(y) **O**(ur) + **Cpl. **(corporal) *in* ***(guinea)** [anag:*new*]