Residents in south-east Queensland are being warned not to go outside if they don’t need to, with the “unprecedented” thick smoke hanging over the region now considered a risk to public health.

Residents of Brisbane, Ipswich and the Gold Coast in particular have been issued a general warning on Monday, with residents urged not to go outside unless they have to.

Queensland’s chief health officer, Dr Jeanette Young, said the warning goes beyond those with the usual risk factors, with the smoke so thick and persistent that it was now a risk to everybody.

A smoke haze blankets Brisbane CBD on Monday morning. Twitter - @minimadclaire

“The air quality in Brisbane, Ipswich and the Gold Coast is now at a level where I’m recommending if you can stay indoors, that’s what you should be doing,” Dr Young said.

“You definitely shouldn’t be doing any major physical exertion outside – this is not the time to go for a run, this is the time to stay indoors.”

The department of environment’s live air quality monitor lists most areas of greater Brisbane and the Gold Coast as having “very poor” quality air.

The warning comes following a weekend that saw many parts of the south-east region hit by large bushfires, with smoke from large bushfires in NSW also contributing to the haze.

The fire danger is expected to increase over the next 48 hours, and Dr Young warned that the risk from smoke pollution to public health would continue for at least as long.

"This is quite unprecedented; we don’t see such large areas which have such a poor level [of air quality]," she said.

“For the next 24 to 48 hours, and probably longer than that, we’re going to see very poor air quality, and it’s that accumulated poor air quality that is the problem.”

Queensland Health issued an alert over the weekend for anyone in the high-risk categories – the very young, the very old, and people with asthma or other existing lung conditions – to be on high alert.

They’ve now issued a general alert for everyone to be on the lookout for symptoms of respiratory problems, including shortness of breath.

Dr Young said they had already had “a small number” of cases of people succumbing to air quality and having to be treated by medical professionals.

“If this was only for a short term, most people with normal lung function would be able to manage it, but given we know this is going to go on for more than 24 hours, it’s important that everyone consider their risk,” she said.

“If they’re having any difficulties breathing, that of course is an immediate trigger and they need to get help.”

Schools have also been advised not to hold any outdoor activities until the air clears.

If people want advice, or think they’re experiencing milder symptoms, they should call the 13-HEALTH hotline (13 43 25 84) or contact their GP.

Health authorities were working closely with all emergency authorities to keep their predictions about how long the smoke would continue to cause trouble as accurate as possible.