The 12-year-old boy is a student of Vanivilasam Upper Primary School in Padoor.
The teen was initially admitted to a primary health centre at Padoor following fever on June 1.
He was later shifted to a private medical college in Thrissur after his health condition deteriorated on June 2.
Following tests and confirmation of the disease, he was admitted to Amrita Hospital on June 16 in a critical condition.
The hospital authorities said in a communication that his condition improved after one week, reported The Hindu.