The travellers were in hotel quarantine at the Best Western Hotel on Bathurst street in Hobart but are now in the process of being transported to the Royal Hobart hospital.

The tests were returned by a woman and two children who are part of the same family.

The mercy flight from Delhi that landed on Sunday morning had 118 Australian citizens on board.

Premier Peter Gutwein said it was not unusual for returned travellers from overseas to return positive COVID-19 tests and that he was confident the cases would not spread into the Tasmanian community.

"We do not have a community transmission, we do not have COVID in our community," he said.

Director of public health Dr Mark Veitch also said the cases were unlikely to present any further risk.

"There is no risk to everyday Tasmanians," he said.

Ninety-one of the 118 traveller tests have been returned and Dr Veitch said it is possible that when the remaining tests come back there could be more positive results.

"It's possible we will pick up further cases," he said.

On November 13, prior to details of the flights being officially confirmed by the Tasmanian government, Premier Peter Gutwein said all travellers on the flight would be tested before embarking on the journey.

"You need to have a negative test before you can fly," he said.

In today's press conference Mr Gutwein, Dr Veitch and chief medical officer Professor Tony Lawler confirmed that all travellers other than children aged under 12 - in line with standard procedures - were tested prior to embarking on the flight.

Professor Lawler said, "within a matter of days those negative tests can become positive".

Professor Lawler was also confident in the "strict and robust" procedures around isolating and quaratining the three COVID-positive individuals - from when they got off the plane, to when they arrived in Hobart, to their transportation to the hospital.

"The will be transferred by Ambulance Tasmania following strict protocols ... [they will then be] managed in a seperate four bed area," he said.

Professor Lawler said all procedures relating to the care and transportation of the travellers had been "assessed as adequate".

Tasmania Police inspector Brian Edmonds said, on their arrival, health screens were undertaken.

At the time plans for the flight were announced Mr Gutwein said travellers would "need to return a negative COVID-19 test on or after day 10 of their quarantine period before entering our community".

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