Unsurprisingly, the number of visits recorded at the territory's COVID-19 testing sites skyrocketed in the same quarter.

One of the few other areas to see an increase was overnight mental health admissions which rose by 12.3 per cent to hit more than 11,300 days worth of in-bed care.

ACT Health Minister Rachel Stephen-Smith said the report clearly demonstrated the significant impact COVID-19 had on practically all facets of the ACT health system.

Ms Stephen-Smith said the COVID-19 pandemic had reduced admissions due to a number of factors, including a virtually non-existent flu season, the lack of sport leading to fewer injuries and Canberrans having generally quieter lives during those months.

"There were also clearly people that didn't want to be at a hospital, who might have come to the emergency department for something you might think relatively minor who were staying away as well," she said.

During the lockdown period, medical experts expressed concerns the rate of other medical conditions, such as cancer, would increase over time due to people avoiding doctors' surgeries and check-ups.

While there was no data available pertaining to this issue, Ms Stephen-Smith said emergency department presentations had essentially returned to normal, suggesting fewer people were avoiding medical scenarios.

The minister noted the number of Category 1 trauma patients, such as people suffering heart attacks or car crash victims, had not reduced.

The number of elective surgeries performed dropped by 20 per cent in the quarter, primarily due to elective surgeries being cancelled for the majority of the period with surgery numbers returning to normal in June.

Ms Stephen-Smith said 1273 elective surgeries were completed in July and 1243 in August, while 483 long-wait elective surgeries had been performed. She said the health service was on track to deliver more than 16,000 elective surgeries this financial year, meeting a commitment to catch up on missed surgeries.

The report showed between April and June Canberra's walk-in clinics experienced a 56.3 per cent drop in visits, or 12,282 fewer presentations.

However, in the same period COVID-19 testing clinics recorded more than 21,000 visits across the Canberra Hospital, EPIC and Weston Creek testing sites. This was a big jump from the 1620 testing site visits in the previous quarter, although COVID-19 testing only began in Canberra in March.

The data did not cover the spike in testing recorded in July and August after the Victorian COVID-19 outbreak.

The lack of visits to walk-in centres meant waiting times dropped significantly. The median wait times for people to be seen dropped by about 70 per cent from 19 minutes in the January quarter to just six minutes in the April quarter.

Canberra's emergency departments witnessed a smaller, although still significant, drop in presentations due to COVID-19.

There were almost 30,000 emergency department visits in the April quarter, down by more than 6000 or 17.7 per cent. Patients arriving by ambulance were down by 13 per cent at just over 7000.

Ms Stephen-Smith credited ACT health care workers for adapting to the changes presented by COVID-19 and said, despite the fewer admissions, staff coped admirably with extra infection control training and managing visitor restrictions.