Special ballot packs for SA election

South Australia's electoral commission is factoring in the impact of COVID-19, on the March poll. (AAP)

South Australians who contract COVID-19 or are forced into isolation close to the March state election will vote using special ballot packs in a poll that may not be decided for days.

The Electoral Commission of South Australia unveiled its strategy for the March 19 poll on Tuesday after concerns that thousands of people could be denied the right to vote.

Commissioner Mick Sherry says those people who contract the virus or are forced into isolation as close contacts between March 17 and election day will be directed to collect a voting pack from designated virus testing sites or a site where rapid antigen tests are distributed.

Those packs can then be returned by post.

Those people forced into isolation between March 7 and March 17, will be able to apply for a postal vote in the usual way.

"This is a unique solution that has not been implemented anywhere in Australia before," Mr Sherry said.

The commissioner said it was unclear how many people would need to use the new arrangements but confirmed a significant increase in postal and pre-poll voting was expected.

Voters affected by COVID-19 just before SA's election will be able to use a special ballot pack. (AAP)

That could result in delayed results in some seats where the numbers are close.

"If the election is close we may not know the result as a whole until several days after polling day," Mr Sherry said.

The commissioner said while this year's election would be more complicated and presented a number of challenges, officials were committed to ensuring every eligible South Australian would have the opportunity to vote safely.

Special measures will be used across the state's 690 polling places, with social distancing enforced and everyone required to wear a mask.

Each polling booth will also have a hygiene officer to ensure the voting stations are regularly sanitised.

All staff working at polling booths will be fully vaccinated.

Chief Public Health Officer Nicola Spurrier said the special voting arrangements could also be used by people who wake up on election day with some COVID-19 symptoms.

"We are very pleased with the outcome of all the work that's been put in," she said.