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Fungal Growth in Carpets - Should You Be Worried?

Uncategorized Mar 19, 2020

The implications of carpet on the indoor microflora

On this week's livestream I'm going to cover the topic of microbial contamination in carpet. In Australia, with over 17% of insurance claims being water-related, the probability of your carpet being water-damaged and mould-affected is high.  However, carpet offers slip resistance, makes floors quiet to walk on and is an interior design feature in many homes and work places. A recent paper in the March 2020 edition of the journal: Building and Environment  revealed some interesting highlights.  Did you know that:

  • carpets are common reservoirs for the uptake and sustained release of both chemical and biological agents
  • carpets can emit chemicals just by being inside your home and can support other chemical transformations
  • In comparison with hard floors, carpets tend to cause more dust re-suspension
  • There are sustainability issues around carpet maintenance, replacement and how to dispose of old carpets 

Floor coverings and water damage

Now, consider the context that asthma costs the community billions of dollars every year and that approx. 35% of asthma cases are caused by mould and dampness (tune in for these references!).

You should be aware that there are 3 main types of carpets: nylon, wool and polypropylene. Which one is better or worse for your respiratory health? What does dust do to the ability of your carpet to induce asthma? What does the amount of humidity do? These are some of the key questions we're going to answer in today's livestream.

Which carpet type is better for mould sensitive people?

Once you know which carpet, which humidity and what other factors impact on your carpet cleanliness, I'm then going to discuss which cleaning methods are best for removing these microbial contaminants.

As part of the weekly 'Breaking News' segment, there a fascinating new paper that's come out that explains how mould damages the lung. This paper provides fundamental evidence in support of the reasons that even low levels of mould can cause harm top people. We're also going to review 2 papers that have come out about the COVID-19 pandemic. The first is a review of what we know of the medical journey for some of the first virus-infected patients in China. This information showed that severe pulmonary disease is the #1 reason for admission to the intensive care unit (ICU). Viral infections (and before COVID-19) became the central worry on all our minds, the risk from severe influenza pneumonia resulting in acute respiratory distress syndrome (ARDS) may in fact be made worse by Aspergillus infections. The relationship of co-infections with other pathogens like bacteria and fungi cannot be underestimated with COVID-19.


YouTube Link:


Dannemiller K, Weschler C, Peccia J. Fungal and bacterial growth in floor dust at elevated relative humidity levels. Indoor Air. 2016;27(2):354-363. doi:10.1111/ina.12313.

Nastasi N, Haines S, Xu L et al. Morphology and quantification of fungal growth in residential dust and carpets. Build Environ. 2020;174:106774. doi:10.1016/j.buildenv.2020.106774

Wiesner D, Merkhofer R, Ober C et al. Club Cell TRPV4 Serves as a Damage Sensor Driving Lung Allergic Inflammation. Cell Host Microbe. 2020. doi:10.1016/j.chom.2020.02.006

Moriello K. Decontamination of carpet exposed to Microsporum canis hairs and spores. J Feline Med Surg. 2016;19(4):435-439. doi:10.1177/1098612x16634390

Tursynbek Nurmagambetov, Robin Kuwahara, Paul Garbe. The Economic Burden of Asthma in the United States, 2008 - 2013. Annals of the American Thoracic Society, 2018; DOI: 10.1513/AnnalsATS.201703-259OC

The National Asthma Council Australia. Published 2020. Accessed March 18, 2020.

Klepeis, N., Nelson, W., Ott, W., Robinson, J., Tsang, A., Switzer, P., et al. (2001). The National Human Activity Pattern Survey (NHAPS): A resource for assessing exposure to environmental pollutants. Journal of Exposure Analysis and Environmental Epidemiology, 11(3). LBNL Report #: LBNL-47713. Retrieved from

Bruce P. Lanphear, Robert S. Kahn, Omer Berger, Peggy Auinger, Steven M. Bortnick and Ramzi W. Nahhas. Contribution of Residential Exposures to Asthma in US Children and Adolescents. Pediatrics June 2001, 107 (6) e98; DOI:

Mudarri D. Valuing the Economic Costs of Allergic Rhinitis, Acute Bronchitis, and Asthma from Exposure to Indoor Dampness and Mold in the US. J Environ Public Health. 2016;2016:1-12. doi:10.1155/2016/2386596

Rodriguez-Morales AJ, Cardona-Ospina JA, Gutiérrez-Ocampo Estefaní, Villamizar-Peña R, Holguin-Rivera Y, Escalera-Antezana JP, Alvarado-Arnez LE, Bonilla-Aldana DK, Franco-Paredes C, Henao-Martinez AndréF, Paniz-Mondolfi A, Lagos-Grisales GJ, Ramírez-Vallejo E, Suárez JA, Zambrano LI, Villamil-Gómez WE, Balbin-Ramon GJ, Rabaan AA, Harapan H, Dhama K, Nishiura H, Kataoka H, Ahmad T, Sah R, On behalf of the Latin American Network of Coronavirus Disease 2019-COVID-19 Research (LANCOVID-19), Clinical, laboratory and imaging features of COVID-19: A systematic review and meta-analysis, Travel Medicine and Infectious Disease (2020), doi:

Watch the Livestream on Fungal Growth in Carpets and what this means for your health:

Every week, I do live streams on public health topics. Join me on Facebook

Dr. Cameron Jones


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