Victoria’s Chief Health Officer has issued a warning on a measles outbreak, possibly stemming from the Philippines, that may have infected Christmas shoppers at Melbourne’s biggest shopping centre.

A 21-year-old Hoppers Crossing man, who was at Chadstone Shopping Centre in Melbourne for three hours in the middle of Boxing Day, may have infected others with measles before he was diagnosed, Dr Rosemary Lester said.

She said the man was likely to have caught measles at an international dance competition in NSW last month, attended by more than 2000 people.

The eleventh case has been diagnosed in New Zealand, with further reports from NSW and South Australia.