The detections, found from September 19 to 22, could be an undiscovered new case or cases, or they could be the result of one or more people in these areas who have recovered from COVID-19 but are still shedding the virus.
Anyone who lives in, works in or has visited Seymour is urged to watch for the mildest of COVID-19 symptoms and to get tested as soon as possible if symptoms develop.
Restrictions will ease slightly across Victoria from September 29, when the state is forecast to have 80 per cent of its population with at least one COVID-19 vaccination.
But Mitchell Shire will remain in lockdown on the same restrictions as metropolitan Melbourne, excluding the curfew.
Mitchell Shire added five cases of COVID-19 on September 28 with health authorities saying the risk of seeding from suburbs in Melbourne’s north with high case numbers remains a concern.
Victoria's COVID-19 response commander Jeroen Weimar pleaded with regional businesses to do more to prevent seeding from Melbourne by restricting visits from remote staff, consultants or trainers.
The single dose vaccination rate in Mitchell Shire is at 78.4 per cent and second dose is at 46.1 per cent.
In Strathbogie Shire, 86.6 per cent have received their first dose and 57.4 per cent are fully vaccinated.
Another 867 new locally acquired COVID-19 infections, 149 new local cases reportable on previous days, and four further deaths were reported on September 28.
The state is now host to more than 9000 active cases, but Premier Daniel Andrews confirmed on September 27 that a number of rules would soon relax, in line with the state’s roadmap out of lockdown.
The state passed 80 per cent single dose vaccination coverage on September 28, and from 11.59 pm outdoor recreation activities like golf and tennis are back on the table.
Residents of locked down areas will be able to travel 15 km from home, up from 10km, while patron caps in regional venues not in lockdown will increase from 20 to 30.
Masks will also not be required for some beauty services like facials and beard trimming in regional Victoria.
For more information on wastewater testing, visit coronavirus.vic.gov.au/wastewater-testing
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