South Australia (SA) Health Department said that a man in Adelaide had come down with measles while living abroad and could have passed on the disease to others since his arrival.

In the past three weeks, the 23-year-old man went to several areas around inner Adelaide and Unley.

The measles virus can be spread through the air by coughing and sneezing. 

Almost everyone born in the state from 1965 onwards received immunisation shots at birth against the virus. 

SA Health's Stephen Christley advised individuals who might have been in contact with the man to call their general practitioners. 

He said people who might have come in contact with the man should either make arrangements to see a doctor or perhaps let the doctor come over and do a check-up “in a way that doesn't put [them] in contact with people who are not immunised."

Mr. Christley emphasised how measles is “very infectious,” having the capacity to infect any person who has failed to have vaccination and who comes in contact with an infected individual.

He said that the measles virus “can make people quite unwell.” Those born after 1965 comprise a “real risk group” because they most likely have not received immunisation and have not had been exposed to the virus, he said.