A measles outbreak linked to a South Australian high school has grown to five cases, with health authorities now tracing contacts at an Adelaide hospital after the latest patient spent more than 24 hours in its emergency department.
SA Health on Friday confirmed a person in their 40s had contracted the infectious disease after a known exposure to the original Brighton Secondary School case.
The latest infection brings the school cluster to five cases and South Australia’s total number of measles cases this year to nine.
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The patient, who remains in a stable condition in hospital, spent extended periods at an emergency department before receiving a diagnosis, prompting a contact-tracing effort.
Chief Public Health Officer Nicola Spurrier said the case was linked to the outbreak that began after an overseas traveller tested positive for measles earlier this month.
Three students subsequently contracted the virus.
According to SA Health, the fifth patient was in The Queen Elizabeth Hospital emergency department waiting room for about five hours from 5.15pm Wednesday before being moved to the department’s fast-track area.
The patient then remained in that area from 9.45pm until 8.15pm the following day.
Spurrier said the lengthy stay meant a number of people could have been exposed.
“It’s not always straightforward when you see a patient what the diagnosis is... The important thing was these doctors did think of measles and did take the swab,” she said.
The Queen Elizabeth Hospital is among dozens of newly identified exposure sites linked to the case.
Others include a pharmacy at Fulham Gardens, two SA Pathology collection centres, Westfield Marion and Harbour Town shopping centres and Morphett Vale Stadium.
Spurrier said the size of the cluster was concerning.
“We haven’t seen a cluster with this amount of spread for some time but it is in a way inevitable because there is so much measles overseas,” she said.
Contact tracers are now working through hospital records to identify anyone who may have been exposed while the patient was in the emergency department.
“They are meticulously going through their records to look for the contact details of anybody who was in the emergency department or the area they call the fast-track area and being able to send out messages directly to those people,” Spurrier said.
Health authorities are also assessing whether any hospital staff may have been exposed, although SA Health requires workers to be vaccinated against infectious diseases including measles.
Anyone who attended an exposure site is being urged to monitor for symptoms including fever, cough, runny nose, conjunctivitis and a red rash that spreads across the body.
Spurrier said symptoms typically developed about 10 days after exposure but could take anywhere between seven and 18 days to appear.
“If you do develop any symptoms at all, please get yourself tested but we do ask for you to ring ahead to the doctor or the hospital so they know you may have been exposed so we can put precautions in place,” she said.
She also urged South Australians to check their vaccination status, those born from 1966 onwards who may have received only one dose of the measles vaccine.
Australian Medical Association SA president Peter Subramaniam said the outbreak was concerning but should not cause panic.
“The normal course of events if you get two vaccines as a child at 12 months and 18 months, those two doses protect about 99 per cent of people for life,” he said.
“To protect the people who are most at risk, the rest of us have to make sure we get vaccinated.”