Molecular epidemiology and genetic diversity of norovirus infection in children with acute gastroenteritis in Bangladesh, 2014-2019.

Acute gastroenteritis (AGE) is one of the most common diseases in children, and it continues to be a significant cause of morbidity and mortality worldwide. Norovirus is one of the major enteropathogens associated with both sporadic diarrhea and outbreaks of gastroenteritis. This study aims to investigate genotype diversity and molecular epidemiology of norovirus in Bangladesh. A total of 466 fecal specimens were collected from January 2014 to January 2019 from children below 5 years old with AGE in Bangladesh. All samples were analyzed by reverse transcriptase polymerase chain reaction to detect norovirus, and sequence analysis was conducted if found positive. Norovirus was detected in 5.1% (24 of 466) fecal specimens. Norovirus genotype GII.7 was predominant (62.5%, 15 of 24), followed by GII.3 (37.5%, 9 of 24). Coinfection between rotavirus and norovirus was found in 7 of 24 positive cases. Diarrhea (93.7%) and dehydration (89%) were the most common symptoms in children with AGE. About 80% of the positive cases were detected in children aged under 24 months. One seasonal peak (87.5% infection) was detected in the winter. This study suggests that norovirus continues to be one of the major etiologies of children AGE in Bangladesh. This study will provide a guideline to assess the burden of norovirus infection in Bangladesh, which will assist to combat against AGE.

Molecular and epidemiological trends of human bocavirus and adenovirus in children with acute gastroenteritis in Bangladesh during 2015 to 2019.

Virus associated diarrhea remains one of the leading causes of children morbidity and mortality in Bangladesh. Human bocavirus (HBoV) has been reported as a potential pathogen of children's diarrhea worldwide. However, due to its frequent association with other gastroenteric pathogens, its role as diarrhea causative agent remains to be defined. This study focuses to detect the incidence of HBoV and adenovirus (AdV) and to determine the molecular and epidemiological characteristics of HBoV and AdV. Between January 2015 to January 2019, 290 fecal specimens were collected from diarrheal children in Bangladesh. All fecal specimens were tested for HBoV and AdV by conventional polymerase chain reaction and sequencing methods. HBoV was detected in 7.24% (21 of 290) of the stool samples, as a sole virus in 71.42% (15 of 21) of the positive samples. AdV was detected in 4.82% (14 of 290) of the samples. The most common clinical symptoms of HBoV infected patients were diarrhea (100%) and vomiting (57%). All of the isolates of HBoV were from HBoV1 and AdV were from AdV41, AdV5, AdV7, and AdV8. To the best of our knowledge, this is the first epidemiological and molecular analysis report of HBoV from clinical specimens in Bangladesh. In the future, more studies are needed to clarify the role of HBoV as diarrheal pathogens.

Microbial- and Plant-Derived Bioactive Peptides and Their Applications against Foodborne Pathogens: Current Status and Future Prospects.

Bioactive peptides (BAPs) obtained from plants and microbes have been thoroughly explored and studied due to their prophylactic properties. The use of BAPs seems to be a promising substitute for several currently available antibiotics because of their antimicrobial properties against foodborne pathogens. BAPs have several other useful properties including antitumor, antihypertensive, antioxidant, antiobesity, and antidiabetic activities. Nowadays, scientists have attempted to recombinantly synthesize bioactive peptides to study their characteristics and potential uses, since BAPs are not found in large quantities in nature. Many pathogenic microorganisms including foodborne pathogens are becoming resistant to various antibiotics. To combat these pathogens, scientists are working to find novel, innovative, and safe antimicrobial agents. Plant- and microbe-based BAPs have demonstrated noteworthy antimicrobial activity against a wide range of pathogenic microorganisms, including foodborne pathogens. BAPs can kill pathogenic microorganisms by disrupting membrane integrity, inhibiting DNA and RNA synthesis, preventing protein synthesis, blocking protein activity, or interacting with certain intracellular targets. In addition, the positive effect of BAP consumption extends to gut microbiota modulation and affects the equilibrium of reactive oxygen species in the gut. This article discusses recombinant BAPs, BAPs generated from plants and microbes, and their antimicrobial applications and modes of action for controlling foodborne pathogens.

Impact of meteorological factors and population density on COVID-19 pandemic in Saudi Arabia.

Transmission and increase in cases and fatalities of coronavirus disease-2019 (COVID-19) are significantly influenced by the parameters of weather, human activities and population factors. However, study gap on the seasonality of COVID-19 and impact of environmental factors on the pandemic in Saudi Arabia is present. The main aim of the study is to evaluate the impact of environment on the COVID-19 pandemic. Data were analyzed from January 2020 to July 2021. The generalized estimating equation (GEE) was used to determine the effect of environmental variables on longitudinal outcomes. Spearman's rank correlation coefficient (rs ) was used to analyze the impact of different parameters on the outcome of the pandemic. Multiple sequence alignment was performed by using ClustalW. Vaccination and fatalities (r s = -0.85) had the highest association followed by vaccination with cases (r s = -0.81) and population density with the fatalities (rs  = 0.71). The growth rate had the highest correlation with sun hours (r s = -0.63). Isolates from variant of concern alpha and beta were detected. Most of the reference sequences in Saudi Arabia were closely related with B.1.427/429 variant. Clade GH (54%) was the most prevalent followed by O (27%), GR (9%), G (6%), and S (4%), respectively. Male to female patient ratio was 1.4:1. About 95% fatality and hospitalization were reported in patients aged >60 years. This study will create a comprehensive insight of the interaction of environmental factors and the pandemic and add knowledge on seasonality of COVID-19 in Saudi Arabia.

Prevalence and genetic diversity of rotavirus in Bangladesh during pre-vaccination period, 1973-2023: a meta-analysis.

Introduction: Rotavirus infection is a major cause of mortality among children under 5 years in Bangladesh. There is lack of integrated studies on rotavirus prevalence and genetic diversity during 1973 to 2023 in Bangladesh. Methods: This meta-analysis was conducted to determine the prevalence, genotypic diversity and seasonal distribution of rotavirus during pre-vaccination period in Bangladesh. This study included published articles on rotavirus A, rotavirus B and rotavirus C. We used Medline, Scopus and Google Scholar for published articles. Selected literatures were published between 1973 to 2023. Results: This study detected 12431 research articles published on rotavirus. Based on the inclusion criteria, 29 of 75 (30.2%) studies were selected. Molecular epidemiological data was taken from 29 articles, prevalence data from 29 articles, and clinical symptoms from 19 articles. The pooled prevalence of rotavirus was 30.1% (95% CI: 22%-45%, p = 0.005). Rotavirus G1 (27.1%, 2228 of 8219) was the most prevalent followed by G2 (21.09%, 1733 of 8219), G4 (11.58%, 952 of 8219), G9 (9.37%, 770 of 8219), G12 (8.48%, 697 of 8219), and G3 (2.79%, 229 of 8219), respectively. Genotype P[8] (40.6%, 2548 of 6274) was the most prevalent followed by P[4] (12.4%, 777 of 6274) and P[6] (6.4%, 400 of 6274), respectively. Rotavirus G1P[8] (19%) was the most frequent followed by G2P [4] (9.4%), G12P[8] (7.2%), and G9P[8], respectively. Rotavirus infection had higher odds of occurrence during December and February (aOR: 2.86, 95% CI: 2.43-3.6, p = 0.001). Discussion: This is the first meta-analysis including all the studies on prevalence, molecular epidemiology, and genetic diversity of rotavirus from 1973 to 2023, pre-vaccination period in Bangladesh. This study will provide overall scenario of rotavirus genetic diversity and seasonality during pre-vaccination period and aids in policy making for rotavirus vaccination program in Bangladesh. This work will add valuable knowledge for vaccination against rotavirus and compare the data after starting vaccination in Bangladesh.

Multidrug resistance pattern and molecular epidemiology of pathogens among children with diarrhea in Bangladesh, 2019-2021.

Antimicrobial and multidrug resistance (MDR) pathogens are becoming one of the major health threats among children. Integrated studies on the molecular epidemiology and prevalence of AMR and MDR diarrheal pathogens are lacking. A total of 404 fecal specimens were collected from children with diarrhea in Bangladesh from January 2019 to December 2021. We used conventional bacteriologic and molecular sequence analysis methods. Phenotypic and genotypic resistance were determined by disk diffusion and molecular sequencing methods. Fisher's exact tests with 95% confidence intervals (CIs) was performed. Prevalence of bacterial infection was 63% (251 of 404) among children with diarrhea. E. coli (29%) was the most prevalent. E. coli, Shigella spp., V. cholerae, and Salmonella spp., showed the highest frequency of resistance against ceftriaxone (75-85%), and erythromycin (70-75%%). About 10-20% isolates of E. coli, V. cholerae and Shigella spp. showed MDR against cephem, macrolides, and quinolones. Significant association (p value < 0.05) was found between the phenotypic and genotypic resistance. The risk of diarrhea was the highest among the patients co-infected with E. coli and rotavirus [OR 3.6 (95% CI 1.1-5.4) (p = 0.001)] followed by Shigella spp. and rotavirus [OR 3.5 (95% CI 0.5-5.3) (p = 0.001)]. This study will provide an integrated insight of molecular epidemiology and antimicrobial resistance profiling of bacterial pathogens among children with diarrhea in Bangladesh.

High prevalence of norovirus GII.4 Sydney among children with acute gastroenteritis in Bangladesh, 2018-2021.

BACKGROUND: Active molecular surveillance and rapid diagnosis method to track an outbreak of norovirus in Bangladesh is lacking. This study aims to determine the genotypic diversity, molecular epidemiology and evaluate a rapid diagnosis method. METHODS: A total of 404 fecal specimens were collected from children aged below 60 months from January 2018 to December 2021. All samples were analyzed by reverse transcriptase polymerase chain reaction molecular sequencing of partial VP1 nucleotide. Immunochromatography kit (IC, IP Rota/Noro) was evaluated against reference test method. RESULTS: We found norovirus in 6.7 % (27 of 404) fecal specimens. A wide diversity of norovirus genotype including GII.3, GII.4, GII.5, GII.6, GII.7, and GII.9 were detected. Norovirus strain GII.4 Sydney-2012 was the most predominant (74 %, 20 of 27) followed by GII.7 (7.4 %), GII.9 (7.4 %), GII.3 (3.7 %), GII.5 (3.7 %) and GII.6 (3.7 %), respectively. Co-infection of rotavirus and norovirus (19 [4.7 %] of 404) was the most prevalent. We found higher odds of prolonged health impact [OR 1.93 (95 % CI 0.87-3.12) (p = .001)] among patients with co-infection. The incidence of norovirus was significant among the children below 24 months (p = 0.001). Significant relation of temperature with the cases of norovirus was detected (p = 0.001). The IC kit provided high specificity (99.3 %) and sensitivity (100 %) for the detection of norovirus. CONCLUSIONS: This study will provide an integrated insight on the genotypic diversity and rapid identification method of norovirus in Bangladesh.

Prevalence and impact of long COVID-19 among patients with diabetes and cardiovascular diseases in Bangladesh.

Introduction: Co-prevalence of long-COVID-19, cardiovascular diseases and diabetes is one of the major health challenges of the pandemic worldwide. Studies on long-COVID-19 and associated health outcomes are absent in Bangladesh. The main aim of this study was to determine the prevalence and impact of long-COVID-19 on preexisting diabetes and cardiovascular diseases (CVD) on health outcomes among patients in Bangladesh. Methods: We collected data from 3,250 participants in Bangladesh, retrospectively. Multivariable logistic regression model was used to determine the odds ratio between independent and dependent variables. Kaplan-Meier survival curve was used to determine the cumulative survival. Results: COVID-19 was detected among 73.4% (2,385 of 3,250) participants. Acute long-COVID-19 was detected among 28.4% (678 of 2,385) and chronic long-COVID-19 among 71.6% (1,707 of 2,385) patients. CVD and diabetes were found among 32%, and 24% patients, respectively. Mortality rate was 18% (585 of 3,250) among the participants. Co-prevalence of CVD, diabetes and COVID-19 was involved in majority of fatality (95%). Fever (97%), dry cough (87%) and loss of taste and smell (85%) were the most prevalent symptoms. Patients with co-prevalence of CVD, diabetes and COVID-19 had higher risk of fatality (OR: 3.65, 95% CI, 2.79-4.24). Co-prevalence of CVD, diabetes and chronic long-COVID-19 were detected among 11.9% patients. Discussion: Risk of hospitalization and fatality reduced significantly among the vaccinated. This is one of the early studies on long-COVID-19 in Bangladesh.

Genomic surveillance, evolution and global transmission of SARS-CoV-2 during 2019-2022.

In spite of the availability of vaccine, the health burden associated with the COVID-19 pandemic continues to increase. An estimated 5 million people have died with SARS-CoV-2 infection. Analysis of evolution and genomic diversity can provide sufficient information to reduce the health burden of the pandemic. This study focused to conduct worldwide genomic surveillance. About 7.6 million genomic data were analyzed during 2019 to 2022. Multiple sequence alignment was conducted by using maximum likelihood method. Clade GK (52%) was the most predominant followed by GRY (12%), GRA (11%), GR (8%), GH (7%), G (6%), GV (3%), and O (1%), respectively. VOC Delta (66%) was the most prevalent variant followed by VOC Alpha (18%), VOC Omicron (13%), VOC Gamma (2%) and VOC Beta (1%), respectively. The frequency of point mutations including E484K, N501Y, N439K, and L452R at spike protein has increased 10%-92%. Evolutionary rate of the variants was 23.7 substitution per site per year. Substitution mutations E484K and N501Y had significant correlation with cases (r = .45, r = .23), fatalities (r = .15, r = .44) and growth rate R0 (r = .28, r = .54). This study will help to understand the genomic diversity, evolution and the impact of the variants on the outcome of the COVID-19 pandemic.

Impact of Zinc, Vitamins C and D on Disease Prognosis among Patients with COVID-19 in Bangladesh: A Cross-Sectional Study.

Vitamin C, (ascorbic acid), vitamin D (cholecalciferol) and zinc (zinc sulfate monohydrate) supplements are important in immunity against coronavirus disease-2019 (COVID-19). However, a limited number of studies have been conducted on the association of vitamins and supplements with the reduced risks of COVID-19 infection. This study aims to evaluate the association of vitamins and supplements as treatment options to reduce the severity of COVID-19. Data were collected from 962 participants from 13 December 2020 to 4 February 2021. The presence of COVID-19 was confirmed by qRT-PCR. The Chi-square test and multivariate regression analyses were conducted. The ratio of uptake of vitamin C:vitamin D:zinc was 1:1:0.95. Uptake of vitamin C, vitamin D and zinc were significantly associated with the reduced risk of infection and severity of COVID-19 (OR: 0.006 (95% CI: 0.03-0.11) (p = 0.004)) and (OR: 0.03 (95% CI: 0.01-0.22) (p = 0.005)). The tendency of taking supplements was associated with the presence of infection of COVID-19 (p = 0.001), age (p = 0.02), sex (p = 0.05) and residence (p = 0.04). The duration of supplementation and medication was significantly associated with reduced hospitalization (p = 0.0001). Vitamins C, D and zinc were not significantly (p = 0.9) associated with a reduced risk of severity when taken through the diet. Hospitalization (p = 0.000001) and access to health facilities (p = 0.0097) were significantly associated with the survival period of the participants. Participants with better access to health facilities recovered early (OR: 6.21, 95% CI 1.56-24.7). This study will add knowledge in the field of treatment of COVID-19 by using vitamins and zinc supplements.

Antibacterial activity of natural spices on multiple drug resistant Escherichia coli isolated from drinking water, Bangladesh.

BACKGROUND: Spices traditionally have been used as coloring agents, flavoring agents, preservatives, food additives and medicine in Bangladesh. The present work aimed to find out the antimicrobial activity of natural spices on multi-drug resistant Escherichia coli isolates. METHODS: Anti-bacterial potentials of six crude plant extracts (Allium sativum, Zingiber officinale, Allium cepa, Coriandrum sativum, Piper nigrum and Citrus aurantifolia) were tested against five Escherichia coli isolated from potable water sources at kushtia, Bangladesh. RESULTS: All the bacterial isolates were susceptible to undiluted lime-juice. None of them were found to be susceptible against the aqueous extracts of garlic, onion, coriander, pepper and ginger alone. However, all the isolates were susceptible when subjected to 1:1:1 aqueous extract of lime, garlic and ginger. The highest inhibition zone was observed with lime (11 mm). CONCLUSION: Natural spices might have anti-bacterial activity against enteric pathogens and could be used for prevention of diarrheal diseases. Further evaluation is necessary.

Prevalence and impact of diabetes and cardiovascular disease on clinical outcome among patients with COVID-19 in Bangladesh.

BACKGROUND: Patients with coronavirus disease-2019 (COVID-19) with preexisting diabetes and cardiovascular metabolic diseases have higher fatality rate. The circulation of new variants with emerging clinical characteristics requires more studies focusing the impact of preexisting health conditions on outcome of COVID-19 accurately. AIMS: Main aim of this study was to investigate the impact of diabetes and cardiovascular disease (CVD) on disease prognosis and severe health outcomes among patients with COVID-19. METHODS: A retrospective study was performed on 799 patients with COVID-19 during December 10, 2020, to February 10, 2020 in Bangladesh. Logistic regression analysis was performed for age, sex, diabetes, CVD and symptoms on fatality. Kaplan-Meier survival analysis was conducted to predict the survival rate. RESULTS: Fatality was detected in 40% (318 of 799) patients with COVID-19. Among 318 fatalities, 90.6% were detected in patients with CVD and 74.5% in patients with diabetes. Case fatality rate was highest in patients with COVID-19, CVD and diabetes (94, 184 of 195). Fever (91%) and dry cough (71%) were the most frequent symptoms. CVD (42.2%), diabetes (32.7%) and obesity (18%) were prevalent. The highest odds of risk was detected in patients with COVID-19, CVD and diabetes (OR: 6.98, 95% CI, 4.21 to 7.34). Female patients had the highest survival rate. CONCLUSIONS: In this study, 318 fatality was seen in 799 patients with COVID-19. The highest odds of fatality risk was detected in patients with COVID-19, CVD and diabetes. The risk increased many folds when CVD and diabetes coexisted in patients.

Environmental correlation and epidemiologic analysis of COVID-19 pandemic in ten regions in five continents.

BACKGROUND: Coronavirus disease-2019 (COVID-19) has caused worldwide health emergencies during the last 6 months of 2020. Within very short time, severe acute respiratory coronavirus-2 (SARS-CoV-2) has infected over 64,516,333 people with 1,493,264 fatalities in 210 countries and regions. Previous studies have reported that environmental factors can affect the viability and transmission of SARS-CoV-2. This study aimed to determine the correlation of environmental factors with COVID-19 pandemic and epidemiology of COVID-19 across nine countries in five continents. METHODS: Both environmental and health data were retrieved from various databases during January 1, 2020 to June 30, 2020. Mean value of environmental factors were calculated for weekly and daily cases and fatalities. Spearman correlation test was conducted. RESULTS: In this study, most of the COVID-19 cases and fatalities were detected from regions (New York, Madrid, Lombardy, London and Sau Paulo) with 7 °C-25 °C mean temperature per day, 3 to 6 mean UV index per day and 14 km/h to 22 km/h mean wind velocity per day. Both cases and fatalities increased significantly after removing lockdown in Bangladesh, India, Brazil and South Africa. Over 50% COVID-19 patients were asymptomatic in every country except Brazil and Australia. Fever (>50%) was the most common symptom followed by cough (45%), tiredness (38%) and sore throat (30%), respectively. In India and Bangladesh over 70% of cases were reported in male. Significant correlation of COVID-19 cases with temperature and UV were detected in London, Lombardy, Madrid, New York and Dhaka. CONCLUSION: This is one of the first cross-country epidemiologic and correlation studies between environmental factors and COVID-19 pandemics. This study will help both local and international health organizations and policy makers to face the COVID-19 challenge.

Characterization of Pathogenic Vibrio parahaemolyticus Isolated From Fish Aquaculture of the Southwest Coastal Area of Bangladesh.

Vibrio parahaemolyticus is a major foodborne pathogen responsible for significant economic losses in aquaculture and a threat to human health. Here, we explored the incidence, virulence potential, and diversity of V. parahaemolyticus isolates from aquaculture farms in Bangladesh. We examined a total of 216 water, sediment, Oreochromis niloticus (tilapia), Labeo rohita (rui), and Penaeus monodon (shrimp) samples from the aquaculture system where 60.2% (130/216) samples were positive for V. parahaemolyticus. Furthermore, we identified 323 V. parahaemolyticus strains from contaminated samples, 17 of which were found positive for trh, a virulence gene. Four isolates out of the 17 obtained were able to accumulate fluid in the rabbit ileal loop assay. The correlation between the contamination of V. parahaemolyticus and environmental factors was determined by Pearson correlation. The temperature and salinity were significantly correlated (positive) with the incidence of V. parahaemolyticus. Most of the pathogenic isolates (94.1%) were found resistant to ampicillin and amoxicillin. O8: KUT was the predominant serotype of the potentially pathogenic isolates. ERIC-PCR reveals genetic variation and relatedness among the pathogenic isolates. Therefore, this region-specific study establishes the incidence of potential infection with V. parahaemolyticus from the consumption of tilapia, rui, and shrimp raised in farms in Satkhira, Bangladesh, and the basis for developing strategies to reduce the risk for diseases and economic burden.

Bioremediation of Hexavalent Chromium by Chromium Resistant Bacteria Reduces Phytotoxicity.

Chromium (Cr) (VI) has long been known as an environmental hazard that can be reduced from aqueous solutions through bioremediation by living cells. In this study, we investigated the efficiency of reduction and biosorption of Cr(VI) by chromate resistant bacteria isolated from tannery effluent. From 28 screened Cr(VI) resistant isolates, selected bacterial strain SH-1 was identified as Klebsiella sp. via 16S rRNA sequencing. In Luria-Bertani broth, the relative reduction level of Cr(VI) was 95%, but in tannery effluent, it was 63.08% after 72 h of incubation. The cell-free extract of SH-1 showed a 72.2% reduction of Cr(VI), which indicated a higher activity of Cr(VI) reducing enzyme than the control. Live and dead biomass of SH-1 adsorbed 51.25 mg and 29.03 mg Cr(VI) per gram of dry weight, respectively. Two adsorption isotherm models-Langmuir and Freundlich-were used for the illustration of Cr(VI) biosorption using SH-1 live biomass. Scanning electron microscopy (SEM) analysis showed an increased cell size of the treated biomass when compared to the controlled biomass, which supports the adsorption of reduced Cr on the biomass cell surface. Fourier-transform infrared analysis indicated that Cr(VI) had an effect on bacterial biomass, including quantitative and structural modifications. Moreover, the chickpea seed germination study showed beneficial environmental effects that suggest possible application of the isolate for the bioremediation of toxic Cr(VI).

Molecular and Epidemiologic Analysis of Diarrheal Pathogens in Children With Acute Gastroenteritis in Bangladesh During 2014-2019.

BACKGROUND: Diarrheal disease is one of the leading causes of childhood morbidity and mortality in the 21st century in developing countries. Mainly infants and young children develop diarrheal diseases. This study aims to determine the incidence of diarrheal pathogens in children in Bangladesh. METHODS: During 2014 to 2019, 387 fecal specimens were collected from children with diarrhea in Bangladesh. Bacterial pathogens were detected by conventional bacteriologic, biochemical and molecular sequence analysis methods. DNA virus and RNA virus (diarrheal viruses) were detected using polymerase chain reaction and reverse transcriptase polymerase chain reaction, respectively and confirmed by molecular sequence analysis. RESULTS: Bacterial infections were detected in 39.27% (152 of 387) of the stool samples. Escherichia coli was the most prevalent (17.3%) followed by Vibrio cholerae (13.5%), Salmonella spp. (4.9%) and Shigella spp. (3.6%). From 387 fecal specimens tested, 42.4% (164 of 387) were positive for viral infections. Rotavirus was the most prevalent (26.3%), followed by adenovirus (5.7%), norovirus (5.4%) and human bocavirus (4.9%). Dual infection between rotavirus and E. coli accounted for the largest portion of coinfection (48%). Diarrhea (77%) and abdominal pain (65%) were most common followed by vomiting (63%), fever (43%) and dehydration (39%). E. coli and V. cholerae were most resistant against ciprofloxacin (62.7%) and tetracycline (88.5%). qnrA and sul4 resistance genes were isolated from these pathogens. CONCLUSIONS: Data from this study underline the high incidence of diarrheal pathogens and presence of antibiotics resistance genes in a pediatric population in Bangladesh.

Bacteriological assessments of foodborne pathogens in poultry meat at different super shops in Dhaka, Bangladesh.

Poultry is now considered as a major fast-growing source of meat in the world. The consumers demand safe and hygienic products without contamination with pathogenic microorganisms when the production and consumption of poultry meat is gradually increasing. The present study was conducted to assess the bacterial contamination of dressed chicken collected from different supershops in Dhaka, Bangladesh. The chicken samples from S1, S2, M1, M2 and A supershops were analyzed to determine the enteropathogenic bacteria in poultry meat. Three genera of bacteria were isolated from all of the chicken meat samples. These enteropathogens from various organs of dressing chickens were also enumerated. The isolates were presumptively identified as E. coli, Salmonella spp., and Shigella spp. by conventional culture method. The three enteropathogens were subjected to PCR assay for their confirmation as virulent enteropathogens. Only E. coli isolates were confirmed as pathogenic E. coli (Enterotoxigenic), other isolates were not confirmed as virulent Salmonella spp., Shigella spp.. Results of this study demonstrated that more cautions are recommended for personnel hygiene in processing and handling of poultry and poultry products to prevent occurrence of enterotoxigenic E. coli in dressed poultry meat sold by the supershops in Bangladesh.

Investigation of Arsenotrophic Microbiome in Arsenic-Affected Bangladesh Groundwater.

Arsenotrophic bacteria contribute to the nutrient cycling in arsenic (As) affected groundwater. This study employed a culture-independent and -dependent investigation of arsenotrophic microbiomes in As affected groundwater samples collected from Madhabpur, Sonatengra, and Union Porishod in Singair Upazila, Manikganj, Bangladesh. Total As contents, detected by Atomic Absorption Spectrophotometry (AAS) of the samples, were 47 µg/L (Madhabpur, SNGW-1), 53 µg/L (Sonatengra, SNGW-2), and 12 µg/L (Union porishod, SNGW-3), whereas the control well (SNGW-4; depths >150 m) showed As content of 6 µg/L. Denaturing Gradient Gel Electrophoresis (DGGE) analysis of the amplified 16S rRNA gene from As-affected groundwater samples revealed the dominance of aerobic bacteria Pseudomonas within heterogeneous bacterial populations. DGGE of heterotrophic enrichments supplemented with arsenite [As (III)] for 4 weeks showed the dominance of Chryseobacterium, Flavobacterium, and Aquabacterium, whereas the dominant genera in that of autotrophic enrichments were Aeromonas, Acinetobacter, and Pseudomonas. Cultured bacteria retrieved from both autotrophic and heterotrophic enrichments were distinguished into nine genotypes belonging to Chryseobacterium, Acinetobacter, Escherichia, Pseudomonas, Stenotrophomonas, Janibacter, Staphylococcus, and Bacillus. They exhibited varying range of As(III) tolerance from 4 to 27 mM. As(III) transformation potential was confirmed within the isolates with oxidation rate as high as 0.143 mM/h for Pseudomonas sp. Sn 28. The arsenotrophic microbiome specifies their potential role in groundwater As-cycling and their genetic information provide the scientific basis for As-bioremediation.