A teenager from Bayside has been left covered in blood after soaking his legs at a beach in Brighton.

Sam Kanizay, 16, had a dip at the Dendy street beach for recovery as he was sore from playing football, but on exiting the ocean after half an hour, he noticed something was not right.

Speaking to 3AW radio program Ross and John, Kanizay says he didn’t think much of the incident at first.

“The cold water basically numbed my legs.” Kanizay told Ross and John. “I thought to myself it was pins and needles, but then it maybe wasn’t pins and needles.”

“I didn’t know what to think about it, it was a bit of a shock.”

The freak incident has caused some confusion among professionals about the nature of the injury.

Michael Brown, a marine biologist with 20 years experience, spoke to the Channel 7 breakfast program Sunrise about the incident.

“I’ve been doing this for coming on 20 years now and I’ve never seen anything like this,” Brown told Sunrise.

A video put up online by Sam’s father, Jarrod Kanizay, shows sea lice slicing up raw meat.

“We sort of had a few people guessing that it was sea lice but no one really had any ideas”, Sam Kanizay told Ross and John.

“We called experts and other hospitals across Melbourne, but there was no real evidence of what it was.”

Currently, Sam is recovering in hospital and doctor’s believe it is still too early to understand what caused the incident.