The trickle of new coronavirus cases in the ACT has become a flood, with the number of positives jumping from nine to 20 overnight.
The latest case is a Lyneham High student who might have been contagious while at the school last week.
This is more than double the number reported on Saturday, when the total was at nine.
ACT Chief Health Officer Kerryn Coleman said seven men and three women aged between 21 and 67 years had tested positive in the past 24 hours.
Before the Lyneham High School case was confirmed late Sunday, eight of the new cases had been linked to overseas travel, one case was a known close contact of a previously confirmed case and one case followed interstate travel from Queensland.
The government would upload relevant flight details to www.health.act.gov.au on Sunday afternoon, and encouraged people who had recently flown to Canberra to check.
Dr Coleman said she did not believe there had been any cases of community transmission in the ACT. Most cases had been people returning home from overseas travel.
However, ACT Health will now expand its testing criteria to bring it more in line with the NSW criteria.
"This will further strengthen our surveillance and enhance our ability to rapidly identify any community transmission early," she said.
"It also acknowledges the pockets of transmission in Australia."
People meeting three new categories will also now be tested in response to the increased availability of testing equipment "and reflecting the increased identification of cases in the ACT and nationally".
People with acute respiratory conditions or an unexplained fever would be tested if they were:
- in hospital
- in a high risk setting, such as an aged care facility, residential care facilities such as boarding schools, or if they had been on a cruise ship
- links to a setting where there had been an outbreak in Australia
She said those settings where outbreaks had occurred in Australia would be collated and posted to the ACT Health website for reference.
These settings would include cruise ship the Ruby Princess, which recently docked in Sydney and discharged about 2700 passengers, including some Canberrans.
Dr Coleman said there had been 2395 negative COVID-19 tests in the ACT as at midday Sunday.
"There are currently two COVID-19 patients being cared for in hospital in Canberra. The remainder of the current cases are isolating at home with the support of ACT Health," she said.
The two patients in hospital were in a stable condition.
She paid tribute to those people who were in self-isolation and their adherence to those requirements. People who had notified ACT Health they were in self-isolation were receiving SMS messages on a daily basis to check on their health and of those in their household.
"We're currently reviewing that to see if there any enhancements we can do to further support people in self-quarantine," she said.
She said the Weston Creek walk-in centre and the new drive-through testing facility in Exhibition Park were best equipped to deal with people who fit the testing criteria.
The ACT Health 24/7 hotline is available to provide advice on 1800 020 080.
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