The Brooklyn middle school student, seventh-grader Omar Rivera, died after contracting methicillin-resistant Staphylococcus aureus, which the city Health Department cited as the "probable cause" of his death, New York Newsday reported Friday.

Health officials said in a statement that fatal staph infections are rare in children and there is "no reason to believe that other children or school employees are at increased risk of staph infection."

Principal Buffie Simmons-Peart said in a letter sent to parents Thursday that the school knew of the death last week but didn't discover the cause until Thursday.

"It is very important for the health of the entire school population that you inform the school nurse of any diagnosed or suspected infectious condition," Simmons-Peart said in the letter.

At least three other MRSA-related deaths have been reported in the past month: in New Hampshire, Virginia and Mississippi, The New York Times reported Thursday.