Currently, the investigation of Legionella ecology falls into two distinct areas of research activity: (1) that Legionella multiply within water sources by parasitizing amoebic or ciliate hosts or (2) that Legionella grows extracellularly within biofilms. Less focus has been given to the overlaps that may occur between these two areas or the likelihood that Legionella employs multiple survival strategies to persist in water sources. It is likely that Legionella interacts with protozoa, bacteria, algae, fungi, etc., and biofilm components in a more complex fashion than multiplication or death due to the presence or absence of single components of these complex microbial systems. This paper addresses gaps that exist in the understanding of Legionella ecology and serves to pinpoint areas of future research. To assume that only one other class of organism is important to Legionella ecology may limit our understanding of how this bacterium proliferates in heated water sources and also limit our strategies for its control in the built environment.

Salmonella contamination of eggs and egg shells has been identified as a public health concern worldwide. A recent shift in consumer preferences has impacted on the egg industry, with a push for cage-free egg production methods. There has also been an increased desire from consumers for raw and unprocessed foods, potentially increasing the risk of salmonellosis. In response to these changes, this review explores the current literature regarding Salmonella contamination of eggs during the production processing through to food handling protocols. The contamination of eggs with Salmonella during the production process is a complex issue, influenced by many variables including flock size, flock age, stress, feed, vaccination, and cleaning routines. Currently there is no consensus regarding the impact of caged, barn and free range egg production has on Salmonella contamination of eggs. The literature regarding the management and control strategies post-collection, during storage, transport and food handling is also reviewed. Pasteurisation and irradiation were identified as the only certain methods for controlling Salmonella and are essential for the protection of high risk groups, whereas control of temperature and pH were identified as potential control methods to minimise the risk for foods containing raw eggs; however, further research is required to provide more detailed control protocols and education programs to reduce the risk of salmonellosis from egg consumption.

This study focused on determining the barriers to effective municipal solid waste management (MSWM) in a rapidly urbanizing area in Thailand. The Tha Khon Yang Subdistrict Municipality is a representative example of many local governments in Thailand that have been facing MSWM issues. In-depth interviews with individuals and focus groups were conducted with key informants including the municipality staff, residents, and external organizations. The major influences affecting waste management were categorized into six areas: social-cultural, technical, financial, organizational, and legal-political barriers and population growth. SWOT analysis shows both internal and external factors are playing a role in MSWM: There is good policy and a reasonably sufficient budget. However, there is insufficient infrastructure, weak strategic planning, registration, staff capacity, information systems, engagement with programs; and unorganized waste management and fee collection systems. The location of flood prone areas has impacted on location and operation of landfill sites. There is also poor communication between the municipality and residents and a lack of participation in waste separation programs. However, external support from government and the nearby university could provide opportunities to improve the situation. These findings will help inform municipal decision makers, leading to better municipal solid waste management in newly urbanized areas.

Strongyloidiasis is a disease caused by soil transmitted helminths of the Strongyloides genus. Currently, it is predominately described as a neglected tropical disease. However, this description is misleading as it focuses on the geographical location of the disease and not the primary consideration, which is the socioeconomic conditions and poor infrastructure found within endemic regions. This classification may result in misdiagnosis and mistreatment by physicians, but more importantly, it influences how the disease is fundamentally viewed. Strongyloidiasis must be first and foremost considered as a disease of disadvantage, to ensure the correct strategies and control measures are used to prevent infection. Changing how strongyloidiasis is perceived from a geographic and clinical issue to an environmental health issue represents the first step in identifying appropriate long term control measures. This includes emphasis on environmental health controls, such as better infrastructure, sanitation and living conditions. This review explores the global prevalence of strongyloidiasis in relation to its presence in subtropical, tropical and temperate climate zones with mild and cold winters, but also explores the corresponding socioeconomic conditions of these regions. The evidence shows that strongyloidiasis is primarily determined by the socioeconomic status of the communities rather than geographic or climatic conditions. It demonstrates that strongyloidiasis should no longer be referred to as a “tropical” disease but rather a disease of disadvantage. This philosophical shift will promote the development of correct control strategies for preventing this disease of disadvantage.

In response to the Coronavirus Disease 2019 (COVID-19) pandemic, current modeling supports the use of masks in community settings to reduce the transmission of SARS-CoV-2. However, concerns have been raised regarding the global shortage of medical grade masks and the limited evidence on the efficacy of fabric masks. This study used a standard mask testing method (ASTM F2101-14) and a model virus (bacteriophage MS2) to test the viral filtration efficiency (VFE) of fabric masks compared with commercially available disposable, surgical, and N95 masks. Five different types of fabric masks were purchased from the ecommerce website Etsy to represent a range of different fabric mask designs and materials currently available. One mask included a pocket for a filter; which was tested without a filter, with a dried baby wipe, and a section of a vacuum cleaner bag. A sixth fabric mask was also made according to the Victorian Department of Health and Human Services (DHHS) guidelines (Australia). Three masks of each type were tested. This study found that all the fabric masks had a VFE of at least 50% when tested against aerosols with an average size of 6.0 µm (VFE(6.0 µm)). The minimum VFE of fabric masks improved (to 63%) when the larger aerosols were excluded to give and average aerosol size of 2.6 µm (VFE(2.6 µm)), which better represents inhaled aerosols that can reach the lower respiratory system. The best performing fabric masks were the cotton mask with a section of vacuum cleaner bag (VFE(6.0 µm) = 99.5%, VFE(2.6 µm) = 98.8%) or a dried baby wipe (VFE(6.0 µm) = 98.5%, VFE(2.6 µm) = 97.6%) in the pocket designed for a disposable filter, the mask made using the Victorian DHHS design (VFE(6.0 µm) = 98.6%, VFE(2.6 µm) =99.1%) and one made from a layer of 100% hemp, a layer of poly membrane, and a layer of cheesecloth (VFE(6.0 µm) = 93.6%, VFE(2.6 µm) = 89.0%). The VFE of two surgical masks (VFE(6.0 µm) = 99.9% and 99.6%, VFE(2.6 µm) = 99.5% and 98.5%) and a N95 masks (VFE(6.0 µm) = 99.9%, VFE(2.6 µm) = 99.3%) were comparable to their advertised bacterial filtration efficacy. This research supports the use of fabric masks in the community to prevent the spread of SARS-CoV-2; however, future research is needed to explore the optimum design in ensuring proper fit. There is also a need for mass education campaigns to disseminate this information, along with guidelines around the proper usage and washing of fabric masks.

Strongyloidiasis is caused by the human infective nematodes Strongyloides stercoralis , Strongyloides fuelleborni subsp. fuelleborni and Strongyloides fuelleborni subsp. kellyi . The zoonotic potential of S . stercoralis and the potential role of dogs in the maintenance of strongyloidiasis transmission has been a topic of interest and discussion for many years. In Australia, strongyloidiasis is prevalent in remote socioeconomically disadvantaged communities in the north of the continent. Being an isolated continent that has been separated from other regions for a long geological period, description of diversity of Australian Strongyloides genotypes adds to our understanding of the genetic diversity within the genus. Using PCR and amplicon sequencing (Illumina sequencing technology), we sequenced the Strongyloides SSU rDNA hyper-variable I and hyper-variable IV regions using Strongyloides -specific primers, and a fragment of the mtDNA cox 1 gene using primers that are broadly specific for Strongyloides sp. and hookworms. These loci were amplified from DNA extracted from Australian human and dog faeces, and one human sputum sample. Using this approach, we confirm for the first time that potentially zoonotic S . stercoralis populations are present in Australia, suggesting that dogs represent a potential reservoir of human strongyloidiasis in remote Australian communities.

Streptococcus pyogenes, (colloquially named “group A streptococcus” (GAS)), is a pathogen of public health significance, infecting 18.1 million people worldwide and resulting in 500,000 deaths each year. This review identified published articles on the risk factors and public health prevention and control strategies for mitigating GAS diseases. The pathogen causing GAS diseases is commonly transmitted via respiratory droplets, touching skin sores caused by GAS or through contact with contaminated material or equipment. Foodborne transmission is also possible, although there is need for further research to quantify this route of infection. It was found that GAS diseases are highly prevalent in developing countries, and among indigenous populations and low socioeconomic areas in developed countries. Children, the immunocompromised and the elderly are at the greatest risk of S. pyogenes infections and the associated sequelae, with transmission rates being higher in schools, kindergartens, hospitals and residential care homes. This was attributed to overcrowding and the higher level of social contact in these settings. Prevention and control measures should target the improvement of living conditions, and personal and hand hygiene. Adherence to infection prevention and control practices should be emphasized in high-risk settings. Resource distribution by governments, especially in developed countries, should also be considered.

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