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This study collected rectal swabs from diarrheal patients and in-house environmental samples from low-income households in Dhaka City, Bangladesh, over a 4-month period and investigated these to determine the domestic transmission pathways of Escherichia coli-associated diarrhea. The environmental samples included swabs from four frequently touched surfaces, drinking water and food. Both the rectal swabs and environmental samples were examined for virulence genes characteristic of diarrheagenic E. coli pathotypes by PCR. In addition, each sample was cultured for E. coli, and the strains were analyzed for virulence profile and subjected to multilocus sequence typing (MLST). The results showed that 31% (73 of 233) of all samples including rectal swabs and household samples were positive for one or more of the diarrheagenic E. coli virulence factors. PCR analyses showed that 28% (10/36) of the rectal swabs, 43% (58/136) of household swabs, 9% (3/32) of the food, and 7% (2/29) of the water samples were positive for various virulence genes. 6 Out of the 36 rectal swab samples and associated household samples were shown to have similar E. coli pathotypic genes, and the drinking vessel surface was identified as the major source of contamination. EAEC and CTEC were the most commonly identified pathotypes in the cultured isolates. The phylogenetic tree constructed by MLST data showed that the diarrheagenic isolates were clustered in several diversified lineages. This study supports the hypothesis that there are high-risk hotspots, particularly those surfaces associated with food consumption, for diarrheagenic E. coli contamination within the household environments of Bangladesh.

The demand for bottled drinking water in Bangladesh is becoming popular due to the lack of safe drinking water sources. The present study was carried out to assess the water quality and public health impacts of local brands of bottled drinking water and tube-well water, compared to the imported ones. Several state-of-the-art techniques were employed to determine the contents of pH, EC, salinity, chloride, nitrates, nitrites, fluoride, sulfates, phosphates, bicarbonate, turbidity, color, total hardness, and total dissolved solids in the studied water samples. The measured data show that the level of dissolved minerals in the local branded bottled water is very low (with an exception for sample codes D1 and D8), while imported brands, Zamzam water, and tube-well water contain satisfactory level of minerals and fulfill Dietary Reference Intake requirements. Total coliform, fecal coliform, and E. coli were found to be absent in local brands of bottled water and tube-well water. On the other hand, concentrations of some radionuclides 40K, 238U, 226Ra, 210Pb, 210Po, 222Rn, 137Cs, and 232Th in local bottled water and tube-well water were found to be less than the permissible level given by WHO (2011). The results reveal that local bottled drinking water manufacturing companies may not be following standard guidelines and quality control steps properly. Thus, improvement in their standard operating process is urgently needed to ensure strict compliance with guidelines set by Bangladesh standards and testing institutions.

As far as comorbidity is concerned, cardiovascular diseases (CVD) appear to be accounted for the highest prevalence, severity, and fatality among COVID 19 patients. A wide array of causal links connecting CVD and COVID-19 baffle the overall prognosis as well as the efficacy of the given therapeutic interventions. At the centre of this puzzle lies ACE2 that works as a receptor for the SARS-CoV-2, and functional expression of which is also needed to minimize vasoconstriction otherwise would lead to high blood pressure. Furthermore, SARS-CoV-2 infection seems to reduce the functional expression of ACE2. Given these circumstances, it might be advisable to consider a treatment plan for COVID-19 patients with CVD in an approach that would neither aggravate the vasodeleterious arm of the renin-angiotensinogen-aldosterone system (RAAS) nor compromise the vasoprotective arm of RAAS but is effective to minimize or if possible, inhibit the viral replication. Given the immune modulatory role of Zn in both CVD and COVID-19 pathogenesis, zinc supplement to the selective treatment plan for CVD and COVID-19 comorbid conditions, to be decided by the clinicians depending on the cardiovascular conditions of the patients, might greatly improve the therapeutic outcome. Notably, ACE2 is a zinc metalloenzyme and zinc is also known to inhibit viral replication.

As far as the comorbidity is concerned, cardiovascular diseases (CVD) appear to be accounted for the highest prevalence, severity, and fatality among COVID 19 patients. A wide array of causal links connecting CVD and COVID-19 baffle the overall prognosis as well as the efficacy of the given therapeutic interventions. At the centre of this puzzle lies ACE2 that works as a receptor for the SARS-CoV-2 and functional expression of which is also needed to minimize vasoconstriction otherwise would lead to high blood pressure. Furthermore, SARS-CoV-2 infection seems to reduce the functional expression of ACE2. Given these circumstances, it might be advisable to consider a treatment plan for COVID-19 patients with CVD in an approach that would neither aggravate the vasodeleterious arm of RAAS nor compromise the vasoprotective arm of RAAS but is effective to minimize or if possible, inhibit the viral replication. A zinc supplement to the selective treatment plan, to be decided by the clinicians depending on the cardiovascular conditions of the patients, is hereafter proposed that might greatly enhance the therapeutic outcome. Notably, ACE2 is a zinc metalloenzyme and zinc is also known to inhibit viral replication.

This study collected rectal swabs from diarrheal patients and in-house environmental samples from low-income households in Dhaka City, Bangladesh, over a 4-month period and investigated these to determine the domestic transmission pathways of Escherichia coli-associated diarrhea. The environmental samples included swabs from four frequently touched surfaces, drinking water and food. Both the rectal swabs and environmental samples were examined for virulence genes characteristic of diarrheagenic E. coli pathotypes by PCR. In addition, each sample was cultured for E. coli, and the strains were analyzed for virulence profile and subjected to multilocus sequence typing (MLST). The results showed that 31% (73 of 233) of all samples including rectal swabs and household samples were positive for one or more of the diarrheagenic E. coli virulence factors. PCR analyses showed that 28% (10/36) of the rectal swabs, 43% (58/136) of household swabs, 9% (3/32) of the food, and 7% (2/29) of the water samples were positive for various virulence genes. 6 Out of the 36 rectal swab samples and associated household samples were shown to have similar E. coli pathotypic genes, and the drinking vessel surface was identified as the major source of contamination. EAEC and CTEC were the most commonly identified pathotypes in the cultured isolates. The phylogenetic tree constructed by MLST data showed that the diarrheagenic isolates were clustered in several diversified lineages. This study supports the hypothesis that there are high-risk hotspots, particularly those surfaces associated with food consumption, for diarrheagenic E. coli contamination within the household environments of Bangladesh.

Whole genome sequencing was utilized to investigate the genomic profile of Vibrio cholerae O1 strains, isolated from symptomatic patients in a low-income urban area of Dhaka, Bangladesh. Comparative genomics using bioinformatics tools were applied to identify major virulence factors, biotype and antimicrobial resistance genes in three V. cholerae O1 strains (VC-1, 2 and 3) isolated from two case patients. A phylogenetic SNP (single nucleotide polymorphism)-based analysis was conducted to infer the relatedness to V. cholerae O1 strains isolated elsewhere. The V. cholerae strains were the El Tor variant carrying ctxB1 (standard classical genotype). SNP-based global phylogeny revealed that the three isolates were strictly clonal and the closest neighbouring genomes were epidemic clones of V. cholerae O1 isolated in 2010 from cholera patients in Pakistan. All strains harboured the integrase gene of the SXT element (intSXT ), antimicrobial resistance genes for aminoglycosides, phenicol, sulphonamide and trimethoprim except VC-1 that lacked sulphonamide resistance genes. The multilocus sequence typing (MLST) revealed that the strains belonged to sequence type, ST69. The study provides knowledge on current genetic traits of clinical V. cholerae O1 circulating in urban household clusters of Bangladesh which may help in predicting emergence of new pandemic strains in Bangladesh. SIGNIFICANCE AND IMPACT OF THE STUDY Vibrio cholerae has frequently experienced genetic changes with rapid evolution of pandemic clones in the Ganges Delta region. Whole genome sequencing can reveal genetic information of current pathogenic V. cholerae in Bangladesh which includes cefotaxime genotypes, virulence factors, altered antimicrobial resistance pattern as well as mobile genetic element compared to global pandemic strains. This study data could be used in planning future surveillance strategies in Ganges Delta region by informing new epidemiology of current outbreak strains.

Dhaka is the largest and fastest-growing urban city in Bangladesh with a population density of 44,500/km2. Dhaka Water Supply and Sewerage Authority (DWASA) is the sole legal entity to develop and maintain a water supply system for city people. 78% DWASA water comes from underground—which leads to incremental depletion of groundwater. In this condition, reducing groundwater dependence and switching to surface water is the only way forward. Growing and increasingly wealthier population, climate change and the urbanization process deteriorate the Shitalakshya River which is the surface water source of DWASA. The purpose of this study was to investigate the DWASA supplied water quality around Dhaka city. Physicochemical and microbiological Parameters were analyzed by American Public Health Association (APHA) standard methods. The measured pH value (6.58-7.03) and Dissolved Oxygen (DO) value (6.10-7.50 mg/L) of samples indicate safe potable water. Calcium and Magnesium were found at a significant level. Both of these elements are essential for the human body. There were no heavy metals contamination in water supplied by DWASA. Total Coliforms and Fecal Coliforms of all samples showed less than 0.2 MPN/mL (most probable number