Wind-driven roof turbines' effectiveness in enhancing household ventilation: a potential tool to reduce tuberculosis infection

Background: South Africa's overburdened healthcare systems have led to criticism of its unsustainable tuberculosis management interventions. In 2011, the National Department of Health implemented an outpatient, decentralised care model, but this increased costs and jeopardised the long-term viability of prevention measures. Home confinement is now recognised as a viable intervention option, when combined with safety precautions such as ventilation and medical support. However, little is known about the risk of infection in this context. Objectives: To assess the effectiveness of wind-driven roof turbines in enhancing ventilation and their potential to lower the risk of Mycobacterium tuberculosis infection in a residential setting. Methods: Eight houses were selected and divided equally into intervention (wind turbines installed) and control groups, using a pairwise comparison method. The CO2 decay method was used as a proxy to determine ventilation in the houses. The wind-driven roof turbines' potential to lower the risk of Mycobacterium tuberculosis infection was stochastically evaluated using the Wells-Riley mathematical model. Results: During two seasons, installation of a roof turbine resulted in twofold ventilation rates compared to the control houses. Consequently, the WellsRiley model predicted a twofold reduction in the probability of infection in the intervention compared to the control households. Conclusion: Low-cost, low-maintenance wind-driven roof turbines are effective in increasing ventilation in houses, and should be considered as an additional layer of protection against Mycobacterium tuberculosis and other infections in residential settings.

Water quality challenges in buildings during prolonged low or no occupancy: a cause for concern during COVID-19 lockdowns and related building closures

Introduction: In compliance with the COVID-19 lockdown restrictions, many nonessential workplaces and public spaces were closed or left sub-operational with no or low occupancy for several months. The abrupt and unprecedented long periods of building closures have raised concerns about the proliferation of opportunistic premise plumbing pathogens that may be a biohazard for returning occupants. Objective: In this review paper, we discuss microbiological water quality concerns during periods of no or low occupancy, as experienced during the COVID-19 lockdowns. Methods: PubMed and Google Scholar databases were searched for peer-reviewed articles using specific keywords. The literature search was extended to grey literature. The paper focuses on Legionella, as a pathogen of concern, in building water systems that are not well managed and the potential risks to workers and other occupants. Results: Most articles suggest a positive relationship between stagnation or reduced water usage and compromised microbiological quality of building water systems, but the effects are site-specific and are associated with biofilm formation and disinfectant decline. Considerations for building water risk assessment are discussed as a decision-making framework for selecting appropriate responses to anticipated changes in water quality. Conclusion: The unprecedented building closures due to COVID-19 lockdowns present a hazardous event likely to impact building water quality. Building owners and facility managers, especially in high-risk settings, should consider conducting risk assessments of water systems during low-occupancy periods to identify potential risks and apply appropriate corrective measures, where necessary.

COVID-19 pandemic: workplace readiness to control and contain the spread of coronavirus

The coronavirus outbreak has been declared a pandemic by the World Health Organization. It is a huge concern to both public and occupational health and is the biggest current threat to the global economy and financial markets. The aim of this paper is to highlight the key occupational health challenges based on available literature and to provide some guidance on preventive measures. A literature search was conducted on PubMed and Google for studies published from January to March 2020. Google translate was used for articles in foreign languages. The literature showed that healthcare workers are a high-risk group, although any worker is at potential risk. The key challenges identified relate to labour rights and sick leave, compensation, impact of quarantine on business continuity, and whether transmission is purely through droplets or if airborne transmission plays a role. The evidence, although limited, provides guidance for slowing down and reducing the risk of spread of the virus