Authorities in NSW are warning residents to treat all bats as if they are rabid.

Over 140 people have been bitten or scratched by bats in the state so far this year, putting them at risk of the rabies-like lyssavirus.

Each of them have been treated with vaccines to try to prevent lyssavirus, and NSW Health wants everyone to be wary of the fatal disease.

The department says anyone who comes into contact with a bat to see their doctor.

“Everyone who gets bitten or scratched by a bat in Australia should have the preventative treatment,” NSW Health director of communicable diseases Dr Vicky Sheppeard said.

“If the infection does develop then it is too late to do anything to cure it.”

Three people died from lyssavirus between 1996 and 2013, all of which came from Queensland.

The best preventative response is a free, four-course vaccine.

NSW Health says up to 200 will have been bitten or scratched by bats by the end of the year, with a spike expected in November due to the local breeding season.

“This is the time when bats are birthing their pups and people do tend to find them on the ground and try to help them,” Dr Sheppeard said.

“But they must remember they shouldn't handle any bat.”