Brisbane residents face the prospect of a snap lockdown if there is any further spread of the coronavirus, after four new cases on Tuesday sent shockwaves through Queensland, which has been COVID-free for the past few weeks.

Amid growing fears the National Rugby League grand final on Sunday could be moved from Brisbane to Townsville, Queensland Premier Annastacia Palaszczuk said the next few days would be crucial to determine if there was a need for tougher restrictions.