Five people have now been diagnosed with Legionnaires’ disease in Sydney's inner west.

News of the fifth case has boosted calls for more efforts in response.

NSW Health says the man in his 80s has been hospitalised after contracting the illness, marking the fifth case of the disease in the area in the past two weeks.

But NSW Health says it is not sure whether the cases can be linked to an ongoing outbreak in nearby Burwood.

The authorities say there are about 60 cases of this particular strain of Legionnaires’ disease each year in NSW.

NSW’s Labor opposition says the Government should establish an air cooling tower registry to help detect and manage outbreaks.

“Labor would like to see the State Government take over control of the inspections, set up a central registry of air cooler towers similar to what exists in Victoria,” Opposition health spokesman Walt Secord said on the weekend.

“Victoria has monitoring under the State Government rather than local government.

“We would also like a central registry so if there's an outbreak health officials will immediately know air cooling towers in the area affected.”

Reports say NSW Health has put together an expert panel to look at options, including any strengthening measures that might be required.