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Household food security in Vietnam remains tenuous. We surveyed 552 households to investigate household food insecurity (HFI) in rural districts in the Vietnamese Mekong Delta. HFI prevalence was 34.4% and 48.4% in the last month and last year respectively. Khmer households were twice as likely to experience HFI compared to their Kinh counterparts. The primary factors associated with HFI were weak livelihood assets including lower natural, financial and human assets (being landless, low incomes), physical and social assets (poor market access, social networks), lower kitchen utensil scores, belonging to a minority and experiencing financial, agricultural and extreme weather shocks.

INTRODUCTION: Household food insecurity and inadequate water, sanitation, and hygiene (WASH) contribute to ill health. However, the interactions between household food insecurity, WASH and health have been rarely assessed concurrently. This study investigated compounded impacts of household food insecurity and WASH on self-reported physical and mental health of adults in the Vietnamese Mekong Delta. MATERIALS AND METHODS: This cross-sectional survey interviewed 552 households in one northern and one southern province of the Vietnamese Mekong Delta. The survey incorporated previously validated tools such as the Short Form 12-item Health Survey, Household Food Insecurity Assessment Scale, and the Access and Behavioural Outcome Indicators for Water, Sanitation, and Hygiene. Physical and mental health were quantified using the physical health composite score (PCS) and mental health composite score (MCS), respectively. These measures were the dependent variables of interest for this study. RESULTS: Statistical analysis revealed that household food insecurity and using <50 litres of water per person per day (pppd) were independently associated with lower PCS (p<0.05), after adjusting for socio-economic confounders. Household food insecurity and lack of food availability, using <50 litres of water pppd, and the use of untreated drinking water were associated with lower MCS (p<0.05), with water usage being an effect modifier of the relationship between household food insecurity and MCS. The results indicate that being food insecure and having limited potable quality water had a compounding effect on MCS, compared to being individually either food insecure or having limited water. CONCLUSION: This study is one of only a few that have established a link between potable water availability, food insecurity and poorer physical and mental health. The results also indicate a need to validate national data with fine-scale investigations in less populous regions to evaluate natio

Wastewater surveillance for pathogens using reverse transcription-polymerase chain reaction (RT-PCR) is an effective and resource-efficient tool for gathering community-level public health information, including the incidence of coronavirus disease-19 (COVID-19). Surveillance of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) in wastewater can potentially provide an early warning signal of COVID-19 infections in a community. The capacity of the world's environmental microbiology and virology laboratories for SARS-CoV-2 RNA characterization in wastewater is increasing rapidly. However, there are no standardized protocols or harmonized quality assurance and quality control (QA/QC) procedures for SARS-CoV-2 wastewater surveillance. This paper is a technical review of factors that can cause false-positive and false-negative errors in the surveillance of SARS-CoV-2 RNA in wastewater, culminating in recommended strategies that can be implemented to identify and mitigate some of these errors. Recommendations include stringent QA/QC measures, representative sampling approaches, effective virus concentration and efficient RNA extraction, PCR inhibition assessment, inclusion of sample processing controls, and considerations for RT-PCR assay selection and data interpretation. Clear data interpretation guidelines (e.g., determination of positive and negative samples) are critical, particularly when the incidence of SARS-CoV-2 in wastewater is low. Corrective and confirmatory actions must be in place for inconclusive results or results diverging from current trends (e.g., initial onset or reemergence of COVID-19 in a community). It is also prudent to perform interlaboratory comparisons to ensure results' reliability and interpretability for prospective and retrospective analyses. The strategies that are recommended in this review aim to improve SARS-CoV-2 characterization and detection for wastewater surveillance applications. A silver lining of the COVID-19 pandemi

Wastewater surveillance for pathogens using the reverse transcription-polymerase chain reaction (RT-PCR) is an effective, resource-efficient tool for gathering additional community-level public health information, including the incidence and/or prevalence and trends of coronavirus disease-19 (COVID-19). Surveillance of SARS-CoV-2 in wastewater may provide an early-warning signal of COVID-19 infections in a community. The capacity of the world’s environmental microbiology and virology laboratories for SARS-CoV-2 RNA characterization in wastewater is rapidly increasing. However, there are no standardized protocols nor harmonized quality assurance and quality control (QA/QC) procedures for SARS-CoV-2 wastewater surveillance. This paper is a technical review of factors that can lead to false-positive and -negative errors in the surveillance of SARS-CoV-2, culminating in recommendations and strategies that can be implemented to identify and mitigate these errors. Recommendations include, stringent QA/QC measures, representative sampling approaches, effective virus concentration and efficient RNA extraction, amplification inhibition assessment, inclusion of sample processing controls, and considerations for RT-PCR assay selection and data interpretation. Clear data interpretation guidelines (e.g., determination of positive and negative samples) are critical, particularly during a low incidence of SARS-CoV-2 in wastewater. Corrective and confirmatory actions must be in place for inconclusive and/or potentially significant results (e.g., initial onset or reemergence of COVID-19 in a community). It will also be prudent to perform inter-laboratory comparisons to ensure results are reliable and interpretable for ongoing and retrospective analyses. The strategies that are recommended in this review aim to improve SARS-CoV-2 characterization for wastewater surveillance applications. A silver lining of the COVID-19 pandemic is that the efficacy of wastewater surveillance was demo

Forty-six bottled water samples representing 16 brands from Dhaka, Bangladesh were tested for the numbers of total coliforms, fecal indicator bacteria (i.e., thermotolerant Escherichia coli and Enterococcus spp.) and potential bacterial pathogens (i.e., Aeromonas hydrophil, Pseudomonas aeruginos, Salmonella spp., and Shigella spp.). Among the 16 brands tested, 14 (86%), ten (63%) and seven (44%) were positive for total coliforms, E. coil and Enterococcus spp., respectively. Additionally, a further nine (56%), eight (50%), six (37%), and four (25%) brands were PCR positive for A. hydrophila lip, P. aeruginosa ETA, Salmonella spp. invA, and Shigella spp. ipaH genes, respectively. The numbers of bacterial pathogens in bottled water samples ranged from 28 ± 12 to 600 ± 45 (A. hydrophila lip gene), 180 ± 40 to 900 ± 200 (Salmonella spp. invA gene), 180 ± 40 to 1,300 ± 400 (P. aeruginosa ETA gene) genomic units per L of water. Shigella spp. ipaH gene was not quantifiable. Discrepancies were observed in terms of the occurrence of fecal indicators and bacterial pathogens. No correlations were observed between fecal indicators numbers and presence/absence of A. hydrophila lip (p = 0.245), Salmonella spp. invA (p = 0.433), Shigella spp. ipaH gene (p = 0.078), and P. aeruginosa ETA (p = 0.059) genes. Our results suggest that microbiological quality of bottled waters sold in Dhaka, Bangladesh is highly variable. To protect public health, stringent quality control is recommended for the bottled water industry in Bangladesh. Key words: bottled water, fecal indicator bacteria, quantitative PCR, bacterial pathogens, public health risk.

Urbanisation and the subsequent increase in impervious land use generate increased urban stormwater which can be recycled viamanaged aquifer recharge (MAR) to supplement more traditional surface or ground water supplies. This paper compares the quality of stormwater from two urban catchments in South Australia to assess the risks, in accordance with the Australian Guidelines for Water Recycling, of recycling stormwater via a limestone aquifer for potable water use. In the regional city of Mount Gambier, stormwater MARin a karstic aquifer has been used to supplement the city's drinking water supply for over 100 years. The source water was generally high quality with some instances of turbidity, iron and lead exceeding the Australian Drinking Water Guidelines (ADWG). Effort wasmade to constrain the estimate of minimum residence time within the karstic aquifer to at least two years for evaluation of the potential for passive treatment of trace organic chemicals in this system. In the second example, a purpose built MAR site in Parafield, a northern suburb of Adelaide, has been designed and operated asa full scale trial to determine if wetland treated urban stormwater can be recovered at a standard which meets the ADWG. Based on the analysis undertaken, the source water was generally of high quality with occasional instances of levels of iron and microbial indicators in excess of the ADWG. After a mean residence time in the aquifer of 240 days, recovered water qualitymet the ADWGwith the exception of iron. However, given the uncertainty in pathogen concentrations in the treated stormwater post-recovery from the aquifer, disinfection and aeration for iron removal would be necessary to ensure that the ADWG were met if the water was to be utilised for potable water supply.

With global freshwater supplies under pressure, viable water reuse methods are being examined to assist in improving water supplies. Municipal effluent is an ideal source for water reclamation as it is consistent in quality and quantity. The health aspects of water reuse have been identified as an issue of concern, in particular the potential presence of enteric viruses. Managed Aquifer Recharge (MAR) is a method that can aid water reclamation by recharging water such as treated effluent into a suitable aquifer. Research into the removal of pathogenic contaminants by natural processes within aquifers, namely the action of autochthonous bacteria, has led to the consideration that MAR could be used to assist in the removal of microbial pathogens. Pathogens have been demonstrated to be removed during residence in groundwater, but the presence of active autochthonous groundwater bacteria are required for significant removal rates to occur. The aim of this research was to investigate the interaction between autochthonous groundwater bacteria (AGB) and the enteroviruses Poliovirus type 1, Coxsackievirus B3 and Adenovirus B41. It was established that these viruses decrease in number in the presence of AGB but the mechanisms causing this decrease are poorly understood. Experiments were designed to examine how the individual AGB caused decay of the viruses. In this study AGB were isolated and tested for their ability in increase the decay of the viruses. It was determined that 27 % (17/63) of the isolated AGB influenced viral decay. The AGB isolates varied in their influence with only 3 out of 17 isolates being able to cause of the decay of both poliovirus and coxsackievirus. Similar variations in decay were observed for adenovirus. Decay times for all three viruses varied amongst the AGB and between the viruses. Experiments were undertaken to characterise the mechanism causing the antiviral activity of four groundwater isolates (1G, 3A, 4B and 9G) under varying conditions a