The measles outbreak in Victoria has gotten worse, with another four cases confirmed in the state.

A Melbourne office building is at the centre of a measles outbreak, with four more confirmed cases in Victoria.

Up to 11 people have now been diagnosed as having measles, with eight of those cases linked to the Collins Square office building at Docklands.

"People who work in or around that area...need to be aware of the signs and symptoms of the disease," Victorian chief health officer Professor Charles Guest said.

Measles has an incubation period of seven to 18 days and people who have visited various locations, including the MCG, during the AFL preliminary final last week may not develop symptoms until mid-October, Professor Guest says.

The highly infectious viral disease can cause serious illness and can lead to complications such as pneumonia.

It starts with common cold symptoms like a runny nose, red eyes and a cough followed by a fever and a rash.

LOCATIONS VISITED BY INFECTIOUS MEASLES PATIENTS

* September 20: Melbourne International Airport, Jetstar flight JQ 26 from Denpasar.
* September 20-22: North Richmond, Southern Cross, Murrumbeena and South Yarra train stations.
* September 22: The Australian Ballet's Alice's Adventures in Wonderland at the State Theatre.
* September 23: AFL Preliminary Final (Gate 5, Level 4) at the MCG, Greville St in Prahran; Chapel St in Windsor; the Maribyrnong Boathouse, The Boulevard in Moonee Ponds.
* September 24: Melbourne International Airport, Qantas Club Lounge (8-10am); Qantas flight QF 29 to Hong Kong; KMart Moonee Ponds; DFO Essendon.