Prevalence, Risk Factors and Impacts Related to Mould-Affected Housing: An Australian Integrative Review

A health inequality analysis of childhood asthma prevalence in urban Australia

BACKGROUND

Long-standing health inequalities in Australian society that were exposed by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic were described as "fault lines" in a recent call to action by a consortium of philanthropic organizations. With asthma a major contributor to childhood disease burden, studies of its spatial epidemiology can provide valuable insights into the emergence of health inequalities early in life.

OBJECTIVE

The aims of this study were to characterize the spatial variation of asthma prevalence among children living within Australia's 4 largest cities and quantify the relative contributions of climatic and environmental factors, outdoor air pollution, and socioeconomic status in determining this variation.

METHODS

A Bayesian model with spatial smoothing was developed to regress ecologic health status data from the 2021 Australian Census against groups of explanatory covariates intended to represent mechanistic pathways.

RESULTS

The prevalence of asthma in children aged 5 to 14 years averages 7.9%, 8.2%, 8.5%, and 7.6% in Sydney, Melbourne, Brisbane, and Perth, respectively. This small inter-city variation contrasts against marked intracity variation at the small-area level, which ranges from 6% to 12% between the least and most affected locations in each. Statistical variance decomposition on a subsample of Australian-born, nonindigenous children attributes 66% of the intracity spatial variation to the assembled covariates. Of these covariates, climatic and environmental factors contribute 30%, outdoor air pollution contributes 19%, and areal socioeconomic status contributes the remaining 51%.

CONCLUSION

Geographic health inequalities in the prevalence of childhood asthma within Australia's largest cities reflect a complex interplay of factors, among which socioeconomic status is a principal determinant.

Impact of climate change on paediatric respiratory health: pollutants and aeroallergens

Paediatric populations are particularly vulnerable to respiratory diseases caused and exacerbated by aeroallergens, pollutants and infectious agents. Worsening climate change is expected to increase the prevalence of pollutants and aeroallergens while amplifying disease severity and causing disproportionate effects in under-resourced areas. The purpose of this narrative review is to summarise the role of anthropogenic climate change in the literature examining the future impact of aeroallergens, pollutants and infectious agents on paediatric respiratory diseases with a focus on equitable disease mitigation. The aeroallergens selected for discussion include pollen, dust mites and mould as these are prevalent triggers of paediatric asthma worldwide. Human rhinovirus and respiratory syncytial virus are key viruses interacting with climate change and pollution and are primary causal agents of viral respiratory disease. Within this review, we present the propensity for aeroallergens, climate change and pollution to synergistically exacerbate paediatric respiratory disease and outline measures that can ameliorate the expected increase in morbidity and severity of disease through a health equity lens. We support shifting from fossil fuels to renewable energy worldwide, across sectors, as a primary means of reducing increases in morbidity.

Substandard housing and the risk of COVID-19 infection and disease severity: A retrospective cohort study

In this study we examine associations between substandard housing and the risk of COVID-19 infection and severity during the first year of the pandemic by linking individual-level housing and clinical datasets. Residents of Chelsea, Massachusetts who were tested for COVID-19 at any Mass General Brigham testing site and who lived at a property that had received a city housing inspection were included (N = 2873). Chelsea is a densely populated city with a high prevalence of substandard housing. Inspected properties with housing code violations were considered substandard; inspected properties without violations were considered adequate. COVID-19 infection was defined as any positive PCR test, and severe disease defined as hospitalization with COVID-19. We used a propensity score design to match individuals on variables including age, race, sex, and income. In the severity model, we also matched on ten comorbidities. We estimated the risk of COVID-19 infection and severity associated with substandard housing using Cox Proportional Hazards models for lockdown, the first phase of reopening, and the full study period. In our sample, 32% (919/2873) of individuals tested positive for COVID-19 and 5.9% (135/2297) had severe disease. During lockdown, substandard housing was associated with a 48% increased risk of COVID-19 infection (95%CI 1.1-2.0, p = 0.006). Through Phase 1 reopening, substandard housing was associated with a 39% increased infection risk (95%CI 1.1-1.8, p = 0.020). The difference in risk attenuated over the full study period. There was no difference in severe disease risk between the two groups. The increased risk, observed only during lockdown and early reopening - when residents were most exposed to their housing - strengthens claims that substandard housing conveys higher infection risk. The results demonstrate the value of combining cross-sector datasets. Existing city housing data can be leveraged 1) to identify and prioritize high-risk areas for future pandemic response, and 2) for longer-term housing solutions.

Damp Buildings: Associated Fungi and How to Find Them

The number of buildings experiencing humidity problems and fungal growth appears to be increasing as energy-saving measures and changes in construction practices and climate become more common. Determining the cause of the problem and documenting the type and extent of fungal growth are complex processes involving both building physics and indoor mycology. New detection and identification methods have been introduced, and new fungal species have been added to the list of building-related fungi. However, the lack of standardised procedures and general knowledge hampers the effort to resolve the problems and advocate for an effective renovation plan. This review provides a framework for building inspections on current sampling methods and detection techniques for building-related fungi. The review also contains tables with fungal species that have been identified on commonly used building materials in Europe and North America (e.g., gypsum wallboard, oriented strand board (OSB), concrete and mineral wool). The most reported building-associated fungi across all materials are Penicillium chrysogenum and Aspergillus versicolor. Chaetomium globosum is common on all organic materials, whereas Aspergillus niger is common on all inorganic materials.

Moisture damage and fungal contamination in buildings are a massive health threat - a surgeon's perspective

OBJECTIVES

Indoor air toxicity is of major public health concern due to the increase in humidity-induced indoor mould exposure and associated health changes. The objective is to present evidence for the causality of health threats and indoor mould exposure.

METHODS

PubMed search on the following keywords: dampness, mould, indoor air quality, public health, dampness, and mould hypersensitivity syndrome, sick building syndrome, and building-related illness as well as information from the health authorities of Bavaria and North Rhine-Westphalia, the Center of Disease Control (CDC), World Health Organisation (WHO), and guidelines of professional societies.

RESULTS

The guidelines of professional societies published in 2017 are decisive for the assessment of the impact of mould pollution caused by moisture damage on human health and for official regulations in Germany. Until 2017, a causal connection between moisture damage and mould exposure could usually only be established for pulmonary diseases. The health risk of fungal components is apparent as documented in the fungal priority pathogens list (FPPL) of the WHO. Since 2017, studies, especially in Scandinavia, have proved causality between moisture and mould exposure not only for pulmonary diseases but also for extrapulmonary diseases and symptoms. This was made possible by new test methods for determining the toxicity of fungal components in indoor air. Environmental medical syndromes, e.g., dampness and mould hypersensitivity syndrome (DMHS), sick building syndrome (SBS), building-related symptoms (BRS), and building-related illness (BRI), and fungal pathogens, e.g., Aspergillus fumigatus, pose a major threat to public health.

CONCLUSION

There is evidence for the causality of moisture-induced indoor moulds and severe health threats in these buildings. According to these findings, it is no longer justifiable to ignore or trivialize the mould contamination induced by moisture damage and its effects on pulmonary and extrapulmonary diseases. The health and economic implications of these attitudes are clear.

The moisture distribution in wall-to-floor thermal bridges and its influence on mould growth

Moisture in building envelopes increases the energy consumption of buildings and induces mould growth, which may be amplified within the area of thermal bridges due to their different hygrothermal properties and complex structures. In this study, we aimed to (1) reveal the moisture distribution in the typical thermal bridge (i.e., wall-to-floor thermal bridge, WFTB) and its surrounding area and (2) investigate the mould growth in a building envelope that includes both a WFTB and the main part of a wall, in a humid and hot summer/cold winter region of China (Hangzhou City). The transient numerical simulations which lasted for 5 years were performed to model the moisture distribution. Simulated results indicate that the moisture distribution presents significant seasonal and spatial differences due to the WFTB. The areas where moisture accumulates have a higher risk of mould growth. The thermal insulation layer laid on the exterior surface of a WFTB can reduce the overall humidity while uneven moisture distribution may promote mould growth and water vapour condensation.