Several Sydney pounds have closed their doors to cats after a highly-contagious and deadly virus resurfaced after 40 years.

A highly-contagious cat virus not seen in Sydney for 40 years has resurfaced in a western Sydney pound.

Blacktown Council's Animal Holding Facility was forced to close its doors to cats after the outbreak of feline panleukopenia virus, commonly referred to as feline enteritis.

"This is a highly contagious, life-threating viral disease for the cat population ... It has not been seen in Sydney for some 40 years, and many people have therefore stopped vaccinating against it," Blacktown Mayor Stephen Bali said in a statement on Tuesday.

"As a result, it is now attacking a largely unprotected cat population."

At least three other pounds and animal facilities are understood to have closed their doors to cats after an outbreak of the virus, including RSPCA centres at Yagoona and Gunnedah and the Animal Welfare League facility at Kemps Creek.

"Please do not bring cats to our Animal Holding Facility until we are sure the epidemic has passed, and because other facilities across Sydney are affected, cat owners need to check the status of any facility where cats are held," Mr Bali said.

Veterinary expert Vanessa Barrs has advised cat-owners to ensure their animals are vaccinated against the disease.

"Disease in cats is caused by two parvoviruses - small DNA viruses. The main one is feline panleukopenia virus but parvoviruses that infect dogs can also cause the disease in cats," Professor Barrs said.