There have been two new COVID-19 cases detected in Katherine in the Northern Territory overnight.
This takes the cluster to 25 confirmed infections, Northern Territory Chief Minister Michael Gunner confirmed.
The new cases are a 33-year-old non-Aboriginal man and a 59-year-old Aboriginal woman.
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The man who tested positive is a health worker, who initially had contact with a positive case as a part of his work.
He had already been classified as a close contact.
Mr Gunner said officials believe he is the first health care worker to be positive for COVID-19 in the Northern Territory.
He is fully vaccinated, however has existing health issues so has been transferred to Royal Darwin Hospital for treatment.
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https://twitter.com/amy_sinclair9/status/1461508720756543488The woman is associated with one of the households which had positive cases, but she had not previously been identified as a contact.
She had a COVID-19 test because she had symptoms.
Health officials are working to determine her vaccination status.
Mr Gunner said the wastewater results for all areas outside of Katherine and Howard Springs have come back negative overnight.
This includes a negative result for Borroloola.
"This is extremely good news," Mr Gunner said.
"However, given there is still uncertainty about this outbreak... we aren't yet in a position to lift the Territory-wide mask mandate early."More wastewater testing results are due tonight.
2891 COVID-19 tests have been conducted in the Northern Territory.
The number of close contacts stands at 373 and officials are yet to locate 14 people.