Melburnians who visited David Jones and the Queen Victoria Market in the lead up to Christmas have been urged to stay on alert for the signs of measles, after two new confirmed cases in less than a week.

In the most recent case, an infected person travelled into the city on the Saturday afternoon before Christmas when the area was packed with shoppers.

Christmas shopping crowds in Bourke Street Mall last week. Credit:Paul Jeffers

It is not yet clear if the two cases are linked, but health department spokesman Bram Alexander said it was likely they were both acquired overseas in places where measles is endemic rather than locally, where Australian children are routinely vaccinated against the illness.

A notice released by the Victorian Department of Health warns people who were at David Jones in Bourke Street or the Queen Victoria Market on Saturday to be on alert for common measles symptoms that include fever, severe coughing, conjunctivitis and rashes.