Teenagers pricked with a syringe at a high school in Sydney’s West will have to wait months to know if they’ve been infected.

Frantic teachers called hundreds of students into an all-school assembly at Plumpton High School to examine them after a teenager pricked his peers in the hands and thighs with a needle.

Police and emergency services say the student brought the syringe into the school and high-fived eight classmates as a school “prank”.

One student says he was shocked this had happened at his school.

Officers are yet to speak to the student involved The Education Department says strong disciplinary action will be taken.

NSW Ambulance Inspector Joe Ibrahim tells Ben Fordham “it was quite chaotic”, with students and parents “anxious and scared”.

He says police located the syringe nearby, but are aware of “where it’s come from”.

“That’s something they’re certainly looking into”.

Click PLAY below to hear the full interview