A vicious beaver that attacked an 8-year-old boy in New Jersey — before the fast-acting victim catapulted it back into a lake in a video that has since gone viral — has tested positive for rabies, authorities said.

The rowdy rodent had already bitten multiple people at Lake Henry in the Continental Soldiers Park complex when it was filmed chasing the young boy out of the water and biting him while he was fishing with his family.

While cops were investigating the attack, they alerted animal control personnel to the beaver, who found that it was exhibiting signs of possible illness, Capt. Michael Blondin of the Mahwah Police Department told NorthJersey.com.

The beaver has since tested positive for rabies, the Mahwah Township Health Department said in a Facebook update on Tuesday.

“Individuals who were bitten are currently receiving treatment. If you have had any contact with this animal, please notify the Mahwah Township Health Department immediately,” the statement continued.

“You will need to be assessed by a doctor for medical treatment. Everyone is advised to avoid wildlife,” it went on.

The unidentified 8-year-old boy was with his family at Lake Henry at around 6 p.m. Sunday “when the beaver exited the lake and charged him,” Capt. Blondin said earlier.

“The child began to run away but tripped. The animal bit the child in the upper thigh and continued to attack him,” he added.

No further updates have been given about his condition.

No details were given on the beaver’s fate but rabies is usually fatal in animals.