Thanks for writing to health care magic.
could be because of several causes.
But the presence of sore throat
suggests it could be because of throat infection
A throat swab for culture and sensitivity and blood investigations like TLC
, CRP, DLC, prescribed by your doctor after physical examination will help in identifying the cause.
Antibiotics prescribed by your doctor after confirmation of diagnosis will help.
Continue to ask further queries as required.
Hope this helps.