Four new cases of coronavirus have been identified since 6pm Monday.
The state's total is now 218 cases, following two new cases on Monday, four on Sunday, and one on Saturday.
Director of public health Mark Veitch said all cases were related to the North-West.
Three were healthcare workers.
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One was a close contact of a confirmed North-West case, but lives in the North.
The four cases are made up of three women and one man.
One is aged in their 20s, one is in their 40s, one is in their 50s, and one is in their 60s.
"A concerted effort is being made to identify any further cases of coronavirus in the North-West," Dr Veitch said.
"Anyone who lives in the North-West who currently, or in the last few days has had respiratory symptoms like a cough, sore throat, runny nose, or fever should arrange testing through the Public Health Hotline on 1800 671 738 or their GP."