Hundreds of education department staff in Tasmania are yet to provide evidence of their coronavirus vaccination status on the eve of the start of the school year.
The island state will on Wednesday become the last jurisdiction to welcome public school students back to the classroom.
The Australian Education Union says about five per cent of the education workforce has yet to provide evidence of a COVID-19 jab, which is mandatory for education department staff.
AEU Tasmania president David Genford said it amounted to the "alarming number" of about 300 staff.
Liberal state government minister Jane Howlett was non-committal when asked whether staff who hadn't provided proof would be asked to step down.
"We have 96 per cent of teachers currently vaccinated. The department will continue to work with the other staff," she told reporters on Tuesday.
Acting Education Minister Jeremy Rockliff said the 96 per cent figure was "very high" and in line with community vaccination rates.
The government insists it is adequately prepared for students to return for term one and has a pool of 1700 relief teachers to call on should teachers be forced into isolation.
Mr Genford said many teachers were feeling anxious and frustrated and there was a shortage of back up school psychologists and social workers.
"Even if they don't feel safe in their workplace, they'll still be there because they don't want the students to have disrupted learning," he said.
"But our concern is what happens when they do get sick when there aren't people there to replace them?"
The state government says 3399 people have registered their interest to work in school-based non-teaching roles.
There were more than 5600 teachers and principals employed by the education department in 2020/21.
Tasmania's back-to-school plan doesn't include surveillance COVID-19 testing of students or teachers, with children advised to take a rapid antigen test when symptomatic.
The government is providing packs to every student containing two RATs, with two more tests available from schools per week if needed.
Public health officials have said surveillance testing, which occurs in NSW and Victoria, is not needed because of the state's lower transmission level.
Tasmania recorded 601 new cases on Tuesday, an increase on daily numbers reported in recent days.
There are 10 people being treated in hospital for the virus, a rise from Monday's figure of eight. One of them is in intensive care.
Five people with the virus are in hospital for unrelated medical conditions.
There are 3302 documented active cases statewide, continuing a broad downward trend over several weeks.
