Stacey Matthews was horrified when she noticed the insidious black substance on her bedroom roof.
The Port Macquarie resident, who lives with her partner and is pregnant with her first child, first discovered the mould after living in the Flynns Beach rental for a couple of months.
"There were only a couple of spots, some little spores and it was easy to come off," she said.
However, after the region was hit with heavy rainfall, the mould became difficult to control.
Despite the couple's best efforts to combat it, the mould continued to spread throughout their home.
"No matter what we did to clean it, it would just come back," she said.
The mould resulted in health issues for Stacey, including congestion and trouble sleeping due to coughing.
"There was a lot in our room," she said.
"The air was quite damp and heavy."
The couple alerted their real estate agent who attempted to get a trade person in to address the issue.
However after weeks of waiting they were forced to leave the rental.
"We were lucky our real estate agent was understanding and helped us to find another place," Stacey said.
It's a story which is becoming a common one, according to mould expert Bob Knuckey who works across the Mid North Coast region and Australia.
Since the March 2021 floods, Bob has been averaging about 20 properties per week to undertake assessments and provide solutions.
"We are frantic and run off our feet," he said.
Majority of properties on the Mid North Coast are experiencing mould problems and Bob said residents might not be aware of the issue, as it could be hidden in their walls.
Due to the cold and wet weather, mould has been able to thrive because houses have been locked up.
"Every house has got it, including our own," Bob said.
People have to change their environment to prevent mould.
"You need to open your windows, need to ventilate and you need to let the sunshine in," Bob said.
Dehumidifiers should also be used to prevent and alleviate any mould challenges.
According to NSW Health, mould is a type of fungi that can be found almost anywhere.
The organisation's website states many different types of mould exist and they all have the potential to cause health problems.
Bob said it's important for visible mould to be cleaned off straight away to ensure it doesn't spread.
"It can proliferate overnight," he said.
Lake Cathie General Practitioner Dr Marian Dover said people who have existing allergies or respiratory conditions, such as asthma, are most susceptible to mould.
Health issues can be triggered by a small amount of mould.
"It doesn't take much," Dr Dover said.
National Asthma Council's Sensitive Choice Program Manager Adele Taylor said winter is a key time when mould creeps in, releasing tiny spores into the air, which can trigger asthma and allergy symptoms.
"For the 2.7 million Australians living with asthma it is important to take control now to ensure you have a healthy home, as higher indoor humidity levels make it easier for mould and dust mites to multiply," she said.
According to NSW Health mould can result in a blocked nose, cough, wheeze, respiratory infection, itchy eyes and skin.
"Breathing in mould spores may cause an asthma attack."
For more information, please visit www.health.nsw.gov.au
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