"The initial test was a weak positive, so we are following due process to continue to check this result," a service spokesperson said in a statement.

"At this stage, further testing looks like it will be negative however we are following due processes that will continue to test it.

"Speculation in any form is not helpful or informative at this time.

"It is possible that this person had the disease previously but are no longer contagious.

"Out of an abundance of caution we treat every suspected case as if it were positive, and undertake contact tracing accordingly."

Earlier, 4.30pm

It's believed the potential COVID-19 case at Ballarat Health Services may be a patient 'shedding' the virus, and may not be a currently active case.

BHS identified the case may be "historic" - that is, it could be someone who has had the virus previously and is continuing to shed the virus, which can appear in testing, according to health authorities.

This does not mean the patient is infectious.

According to the Department of Health and Human Services website, a historical case "requires laboratory suggestive evidence supported by either previous (prior to the past 14 days) clinical evidence; or previous (prior to the past 14 days) epidemiological evidence".

"A historical case should not have any symptoms of COVID-19 (or not have had symptoms of COVID-19 for the past 14 days).

"Both confirmed and historical cases need to be notified to the department."

More information on historic cases is available online.

It's understood the case is not being counted in Victoria's official figures.

The patient's test result is under investigation, and further testing is being carried out, the hospital confirmed earlier.

St John of God Hospital announced it will be changing its visitor restrictions to one visitor per person per day, with maternity patients allowed one support person with no restrictions.

Previously

A potential COVID-19 case at Ballarat Health Services is "under investigation".

The hospital confirmed on Wednesday afternoon that a returned traveller had presented to the hospital overnight, with the COVID test under investigation.

The person is being monitored at home, but where the person returned from has not been released.

It is believed the case might be historic, says the hospital.

As of 3.30pm on Wednesday, nowhere in Ballarat was listed on the DHHS 'exposure sites' list.

A statement released from the hospital said preparations were in place for such instances.

READ THE FULL MEDIA STATEMENT BELOW

"Out of an abundance of caution, the individual and their close contacts are isolating, including any staff and patients who are required to do so. All due processes have been followed with staff and the individual," the hospital said in a statement.

"Ballarat Health Services staff acted promptly and followed standard precautions with regards to the use of personal protective equipment and other processes relating to suspected COVID cases.

"Given the COVID-safe precautions that remain in place across Ballarat Health Services sites, the Base Hospital and ED remain safe for staff, patients, clients and residents. Ballarat Health Services has planned and prepared for situations like this, and this has not impacted our day-to-day operations across the Base Hospital or for those who have emergency needs."

Staff members and a number of patients are in isolation, the release states.

BHS chief executive Dale Fraser said in a statement the "rapidly evolving" situation is a "timely reminder to our community that the pandemic is well from being over and we need to remain vigilant and cautious".

Australian Community Media asked BHS and DHHS the following questions:

Given the growing number of cases in Melbourne, members of the Ballarat community are urged to regularly check the list of COVID-19 exposure sites, and to follow the directions laid out by DHHS if they have attended one of the sites at the date and time listed.

"A returned traveller from overseas who stayed in Hotel Quarantine interstate presented to BHS overnight, and their COVID test result is currently under investigation. Initial investigations suggest that this may be an historic case. Further testing is being carried out.

Out of an abundance of caution, the individual and their close contacts are isolating, including any staff and patients who are required to do so. All due processes have been followed with staff and the individual.

The Grampians Public Health Unit are undertaking contact tracing for this case. This person is being monitored in their home in the community.

Ballarat Health Services staff acted promptly and followed standard precautions with regards to the use of personal protective equipment and other processes relating to suspected COVID cases.

Given the COVID-safe precautions that remain in place across Ballarat Health Services sites, the Base Hospital and ED remain safe for staff, patients, clients and residents. Ballarat Health Services has planned and prepared for situations like this, and this has not impacted our day-to-day operations across the Base Hospital or for those who have emergency needs.

Community members are encouraged to keep an eye on bhs.org.au/covid-19 for news and updates to visitor information as these may change based on the current outbreak in Melbourne.

The welfare of our community, staff, patients, residents and clients continues to be at the forefront of our response to COVID-19. We will continue to enforce strict infection prevention and control measures, along with visitor restrictions and screening at all Ballarat Health Services sites. For more information, visit: http://bhs.org.au/covid-19

Given the growing number of cases in Melbourne, members of the Ballarat community are urged to regularly check the list of COVID-19 exposure sites, and to follow the directions laid out by DHHS if they have attended one of the sites at the date and time listed.

TESTING

It remains extremely important that anyone with even the mildest of symptoms be tested for COVID-19, and stay home until they can be tested, and until they receive their results.

Appointments can be made at UFS Respiratory clinic (15 Errard Street North) on 03 4311 1571. Drive in testing is available without appointment at 4Cyte Pathology Ballarat COVID-19 Collections (630 Skipton Street, Redan). Anyone showing symptoms must self-isolate until they receive their test results, and until their symptoms resolve.

VACCINATION

The latest COVID outbreak has prompted a significant increase in people seeking the vaccine at the Ballarat Health Services Vaccination Clinic (located at the Mercure, 618 Main Road, Ballarat). It is great to see the community rolling up their sleeve - vaccination provides significant protection against the virus and is Australia's ticket out of COVID-19 and a return to normal.

People aged 50 years and over attending the clinic without a booking are likely to experience wait times. The current wait time can be checked at www.coronavirus.vic.gov.au/vaccination-centres. As at 11am today the wait time is 1hr and 30 minutes for people without an appointment.

Eligible people aged under 50 years must make an appointment to receive the Pfizer vaccine. Appointment bookings can be made by calling 1800 675 398 (select options 1, 1, 1). For further information please check our website regularly at bhs.org.au/vaccine

Quotes attributable to Dale Fraser, CEO, Ballarat Health Services:

"This serves as a timely reminder to our community that the pandemic is well from being over and we need to remain vigilant and cautious. This is a rapidly evolving situation, and the Ballarat community is reminded to help stop the spread of COVID-19 by following the restrictions put in place by the Victorian Government, and to visit the Ballarat Health Services website and the Department of Health website for current and accurate information."

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