All Year 7 pupils at QEII High School and their households are being told to self-isolate immediately.
It comes after government confirmed two pupils in that year group at the Peel school have tested positive for Covid-19.
Officials say unless anyone affected has Coronavirus symptoms they should not contact 111 at this time.
Instead affected households are asked to quarantine and await further instructions.
Vampire show featuring Manx ferry cancelled
Did chief minister's message spark fuel panic-buying?
Joe Locke lands purr-fect new role!
Steam Packet fuel surcharge isn't about profit, says chief minister
Ferry crossing delayed by half an hour
Paw-some rescue effort after Milo gets trapped in ravine
New laws for young workers come into force today
Manx Care extends mental health service to more surgeries