A SECOND COVID-19 case in the Gannawarra shire which was revealed in Victorian health department figures last weekend was by Monday revealed to be inactive.

While Gannawarra's first case, a resident who was diagnosed in March, has long since recovered, the second case was newly listed in Saturday's Department of Health and Human Services figures, prompting concern around the district.

Data on a new case listed in the Central Goldfields Shire on Sunday was also revised on Monday.

In Mildura a new case was removed from the department's listing on Tuesday.

A spokesperson for DHHS told the Gannawarra Times that new COVID-19 cases may occur due to coding errors or "reclassification" - where the data on a case previously recorded elsewhere is changed to reflect a person's place of residence.

The figures list cases in the a person's official place of residence regardless of where they are at the time of diagnosis.

The spokesperson warned that the daily figures should be read with caution.

"Data is continually analysed and clarified as our contact tracing teams gather more information – so published numbers are always subject to change," she said.

"Changes to the data can be caused by many reasons, including multiple notifications for the same person and wrong postcodes recorded."

The department sought to reassure residents that as part of its contact tracing, any sites where public exposure may have occurred are contacted and provided with advice about the transmission risks and any cleaning required.

For privacy reasons DHHS does not provide information about individual cases.

Local health services appealed to residents to continue their vigilance in hand-washing, distancing and general awareness of the risks of contracting the disease.