Yarrawonga Health did not conduct testing for a person whose COVID-19 case has been attributed to the Moira local government area.
The health service issued a statement about the active case that the Victorian Department of Health and Human Services listed in its daily report on Tuesday, bringing Moira's tally to 12.
"All follow-up contact tracing is being undertaken by the Department of Health and Human Services," a spokeswoman said.
"The person did not present to Yarrawonga Health for testing and is not known to YH.
"This means that the individual may have been tested at another testing site or via a GP clinic."
Chief executive Ellaine Mallows urged anyone in the community with even mild symptoms - fever, sore throat, cough, shortness of breath, runny nose, and loss of sense of smell or loss of sense of taste - to call (03) 57438132 to arrange a test.
"My message today is simple, get tested if you have symptoms, wear a mask if you are out, and please, if you can stay home, you must stay home," she said.
"We must work together to help stop the spread and protect our community.
"We have seen the distressing consequences of uncontained community transmission and it is time to work together as a community to do everything we can to help stop the spread."
IN OTHER NEWS:
The tally for Moira had remained at 11 since April, but Tuesday's report took the tally to 12.
It was not disclosed by DHHS if the person was tested in Moira and is isolating there.
Greater Shepparton also has one active case attributed to the region (18 confirmed overall).
Mansfield has four active cases listed (eight confirmed overall), rising from one active case and four cases overall on July 21.
An active case for Wodonga remains on the daily report, despite Albury Wodonga Health outlining 25 days have passed without a new case and that there are no active cases.
On Tuesday, Victoria recorded 439 new cases of coronavirus, and 11 new deaths in aged care facilities.