COVID-19 fragments have been detected in wastewater samples taken from Darwin’s Berrimah treatment plant, NT Health has confirmed, suggesting the results could be from interstate freight and transport workers who have not quarantined.
Chief Health Officer Dr Hugh Heggie said the wastewater samples were taken from September 24 to 28 as part of the NT Government’s COVID-19 surveillance program.
“The detection of viral fragments in wastewater can come from someone who has recovered from COVID-19 and, while no longer infectious, can shed fragments of the virus,” Dr Heggie said in a statement.
He said further testing of wastewater across Darwin and in the Berrimah catchment will be undertaken to monitor the situation.
A proper explanation for how the fragments appeared in the area was not provided.
The Berrimah catchment includes the Winnellie and East Arm industrial areas and port, utilised by freight and transport workers, the government said, some of whom travel from interstate.
Dr Heggie called for all workers in freight and transport to follow industry testing regimes which require weekly testing for COVID-19, regardless of whether a person has any symptoms.
“We are aware that in other areas in Australia, freight and transport workers who are required to travel long distances have tested positive to COVID-19,” he said.
It was unclear if Dr Heggie was suggesting there have been unreported cases of COVID in the community.
He reiterated that it is important for all Territorians and visitors to get tested for COVID-19 if showing any symptoms such as a cough, fever, shortness of breath, muscle aches, change in taste or smell and a sore throat – “especially if you live in Darwin or visited between 24 and 28 September.”
The Berrimah Treatment Plant catchment area includes the suburbs of Berrimah, East Arm, and Northcrest.
Dr Heggie said “strict” border controls are still in place for all people travelling to the NT from a declared hotspot or public exposure site.
“The border controls prohibit entry into the NT except for returning residents, or those who have obtained prior approval to enter,” he added.
He said the continued community transmission of COVID-19 in Australia, outside the NT, is a “reminder of the critical need to be double vaccinated.”
“The best way to protect yourself and your loved ones from becoming very unwell or dying from COVID-19, is to get vaccinated.”
NT Health has urged everyone to get their jabs and arrange a COVID test by booking online or contact the COVID-19 Hotline on 1800 490 484.
Wastewater tests conducted
In October 2020, NT Health said wastewater testing would be carried out in the NT “to ensure cases of coronavirus aren’t going undiagnosed.”
However, it only started conducting wastewater testing in June 2021.
The government confirmed traces of COVID-19 at a catchment area near the Howard Springs quarantine facility, which health experts said was to be expected, at the time.
Fragments were only detected in Howard Springs and there has been no other reported detections of COVID-19 in wastewater sampling from other sites in the NT.
On July 9, health authorities lifted coronavirus restrictions in Greater Darwin region and Alice Springs, declaring “no traces of the virus detected in wastewater sources.”
But on July 16, viral fragments were found in Darwin wastewater samples taken from the Ludmilla treatment plant, which were brushed off as potentially originating from former COVID carriers who had been released from the Howard Springs facility.