scholarly journals Characterization of a New and Efficient Polyvalent Phage Infecting E. coli O157:H7, Salmonella spp., and Shigella sonnei

2021 ◽  
Vol 9 (10) ◽  
pp. 2105
Author(s):  
Su-Hyeon Kim ◽  
Damilare Adeyemi ◽  
Mi-Kyung Park
Keyword(s):  
Burst Size ◽  
Genomic Analysis ◽  
Cesium Chloride ◽  
Shigella Sonnei ◽  
Health Concern ◽  
Lytic Phage ◽  
Salmonella Spp ◽  
E Coli ◽  
Significant Public Health ◽  
Ph Range

Ongoing outbreaks of foodborne diseases remain a significant public health concern. Lytic phages provide promising attributes as biocontrol agents. This study characterized KFS-EC3, a polyvalent and lytic phage, which was isolated from slaughterhouse sewage and purified by cesium chloride density centrifugation. Host range and efficiency of plating analyses revealed that KFS-EC3 is polyvalent and can efficiently infect E. coli O157:H7, Salmonella spp., and Shigella sonnei. KFS-EC3 had a latent time of 20 min and burst size of ~71 phages/infected cell. KFS-EC3 was stable and infectious following storage at a pH range of 3 to 11 and a temperature range of −70°C to 60°C. KFS-EC3 could inhibit E. coli O157:H7 growth by 2 logs up to 52 h even at the lowest MOI of 0.001. Genomic analysis of KFS-EC3 revealed that it consisted of 167,440 bp and 273 ORFs identified as functional genes, without any genes associated with antibiotic resistance, virulence, allergenicity, and lysogenicity. This phage was finally classified into the Tequatrovirus genus of the Myoviridae family. In conclusion, KFS-EC3 could simultaneously infect E. coli O157:H7, S. sonnei, and Salmonella spp. with the lowest MOI values over long periods, suggesting its suitability for simultaneous pathogen control in foods.

scholarly journals Free-Living Aquatic Turtles as Sentinels of Salmonella spp. for Water Bodies

2021 ◽  
Vol 8 ◽  
Author(s):  
Sonia M. Hernandez ◽  
John J. Maurer ◽  
Michael J. Yabsley ◽  
Valerie E. Peters ◽  
Andrea Presotto ◽  
...  
Keyword(s):  
Forest Cover ◽  
Genetic Relatedness ◽  
Canopy Cover ◽  
The United States ◽  
Water Bodies ◽  
Health Concern ◽  
Residential Areas ◽  
Salmonella Spp ◽  
Free Living ◽  
Significant Public Health

Reptile-associated human salmonellosis cases have increased recently in the United States. It is not uncommon to find healthy chelonians shedding Salmonella enterica. The rate and frequency of bacterial shedding are not fully understood, and most studies have focused on captive vs. free-living chelonians and often in relation to an outbreak. Their ecology and significance as sentinels are important to understanding Salmonella transmission. In 2012–2013, Salmonella prevalence was determined for free-living aquatic turtles in man-made ponds in Clarke and Oconee Counties, in northern Georgia (USA) and the correlation between species, basking ecology, demographics (age/sex), season, or landcover with prevalence was assessed. The genetic relatedness between turtle and archived, human isolates, as well as, other archived animal and water isolates reported from this study area was examined. Salmonella was isolated from 45 of 194 turtles (23.2%, range 14–100%) across six species. Prevalence was higher in juveniles (36%) than adults (20%), higher in females (33%) than males (18%), and higher in bottom-dwelling species (31%; common and loggerhead musk turtles, common snapping turtles) than basking species (15%; sliders, painted turtles). Salmonella prevalence decreased as forest cover, canopy cover, and distance from roads increased. Prevalence was also higher in low-density, residential areas that have 20–49% impervious surface. A total of 9 different serovars of two subspecies were isolated including 3 S. enterica subsp. arizonae and 44 S. enterica subsp. enterica (two turtles had two serotypes isolated from each). Among the S. enterica serovars, Montevideo (n = 13) and Rubislaw (n = 11) were predominant. Salmonella serovars Muenchen, Newport, Mississippi, Inverness, Brazil, and Paratyphi B. var L(+) tartrate positive (Java) were also isolated. Importantly, 85% of the turtle isolates matched pulsed-field gel electrophoresis patterns of human isolates, including those reported from Georgia. Collectively, these results suggest that turtles accumulate Salmonella present in water bodies, and they may be effective sentinels of environmental contamination. Ultimately, the Salmonella prevalence rates in wild aquatic turtles, especially those strains shared with humans, highlight a significant public health concern.

scholarly journals Antibiotic-resistant Salmonella species and Escherichia coli in broiler chickens from farms, abattoirs, and open markets in selected districts of Zambia

2020 ◽  
Vol 6 (1) ◽  
pp. 13
Author(s):  
Nelson Phiri ◽  
Geoffrey Mainda ◽  
Mercy Mukuma ◽  
Ntazana N. Sinyangwe ◽  
Luke J. Banda ◽  
...  
Keyword(s):  
Public Health ◽  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Broiler Chickens ◽  
Health Concern ◽  
Diffusion Method ◽  
Salmonella Spp ◽  
Antibiotic Resistant ◽  
E Coli ◽  
Open Markets

Objective: Salmonella species and Escherichia coli are major bacterial enteropathogens of worldwide public health importance that cause devastating foodborne diseases, thereby contributing to increased human morbidity and mortality. Both pathogens have also been found to contribute towards the spread of antimicrobial resistance through the food chain, especially in poultry. This study aimed to determine the occurrence of antibiotic-resistant Salmonella spp. and E. coli in broiler chickens at farm level, abattoirs, and open markets in selected districts of Zambia.Methods: A cross-sectional study was undertaken in seven districts of Zambia to determine the resistance profiles of Salmonella spp. and E. coli obtained from broiler chickens at farms, abattoirs, and open markets. A total of 470 samples were collected which include; litter, cloacal swabs, and carcass swabs. Samples were inoculated into buffered peptone water and incubated for 24 hours then sub-cultured onto MacConkey and Xylose Lysine Deoxycholate agar plates. Identification of Salmonella spp. and E. coli was done using the API-20E kit and confirmation by 16S rDNA sequencing. Confirmed isolates were tested against a panel of 09 antibiotics using the Kirby-Bauer disc diffusion method and interpreted according to the Clinical Laboratory Standards Institute guidelines. Data analysis of the antibiotic sensitivity test results was done using WHONET 2018 software.Results: Overall, 4 Salmonella spp. and 280 E. coli were isolated. One of the Salmonella spp. was resistant to ampicillin (25%), amoxicillin/clavulanic acid (25%), and cefotaxime (25%). E. coli antibiotic resistance was highest to tetracycline (81.4%) and 100% susceptibility to imipenem. The antibiotic susceptibility profile revealed 75.7% (237/280) multidrug-resistant (MDR). The highest MDR profile was observed in 8.2% (23/280) isolates in which 6 out of the 9 classes of antibiotics tested were resistant. Out of the 280 isolates, 11.4% (32/280) exhibited Extensive Drug resistance (XDR).Conclusion: The study found antimicrobial resistance to E. coli and Salmonella spp. in market-ready broiler chickens which were resistant to important antibiotics and is of public health concern.

scholarly journals Evaluation of subsurface irrigation on microorganism contamination of romaine lettuce

2020 ◽  
Vol 187 ◽  
pp. 04009
Author(s):  
Rocio G. Reyes Esteves ◽  
Charles P. Gerba ◽  
Donald C. Slack
Keyword(s):  
Drip Irrigation ◽  
Gastrointestinal Disease ◽  
Microbial Pathogens ◽  
Health Concern ◽  
Contaminated Water ◽  
Romaine Lettuce ◽  
Ms2 Bacteriophage ◽  
E Coli ◽  
Significant Public Health ◽  
Subsurface Drip

The use of contaminated water to irrigate crops by surface, sprinkler, or conventional drip irrigation represents a significant public health concern due to the presence of multiple microbial pathogens associated with gastrointestinal disease. In this study, Escherichia coli and MS2 bacteriophage were used as microbial surrogates to evaluate the contamination of romaine lettuce (Lactuca sativa L. var. longifolia) using bottom watering pots simulating a subsurface drip irrigation (SDI) system in a greenhouse. The primary goal was to determine whether the exposure of lettuce plants to E. coli and MS2 would result in detectable levels of these microorganisms associated with the edible portions of plants. Plants were grown in bottom watering pots and were irrigated the last twelve days before harvesting with contaminated water containing E. coli and MS2 phage at 109 CFU/ml and 1011 PFU/ml, respectively. Harvested plants were processed to determine if E. coli or MS2 was associated with the plant surfaces or within the plant tissues. None of the samples was positive for either E. coli or MS2 bacteriophage, suggesting that subsurface irrigation systems effectively reduce the risk of produce-contamination with bacterial and viral pathogens.

scholarly journals Morphological, biological, and genomic characterization of a newly isolated lytic phage Sfk20 infecting Shigella flexneri, Shigella sonnei, and Shigella dysenteriae1

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Bani Mallick ◽  
Payel Mondal ◽  
Moumita Dutta
Keyword(s):  
Burst Size ◽  
Shigella Flexneri ◽  
Alternative Therapy ◽  
Genomic Analysis ◽  
Multidrug Resistant ◽  
Lytic Activity ◽  
Lytic Phage ◽  
Tem Analysis ◽  
Host Interaction ◽  
Outbreak Area

AbstractShigellosis, caused by Shigella bacterial spp., is one of the leading causes of diarrheal morbidity and mortality. An increasing prevalence of multidrug-resistant Shigella species has revived the importance of bacteriophages as an alternative therapy to antibiotics. In this study, a novel bacteriophage, Sfk20, has been isolated from water bodies of a diarrheal outbreak area in Kolkata (India) with lytic activity against many Shigella spp. Phage Sfk20 showed a latent period of 20 min and a large burst size of 123 pfu per infected cell in a one-step growth analysis. Phage-host interaction and lytic activity confirmed by phage attachment, intracellular phage development, and bacterial cell burst using ultrathin sectioning and TEM analysis. The genomic analysis revealed that the double-stranded DNA genome of Sfk20 contains 164,878 bp with 35.62% G + C content and 241 ORFs. Results suggested phage Sfk20 to include as a member of the T4 myoviridae bacteriophage group. Phage Sfk20 has shown anti-biofilm potential against Shigella species. The results of this study imply that Sfk20 has good possibilities to be used as a biocontrol agent.

scholarly journals Sanitary Status and Occurrence of Some Water-Borne Pathogens in Well and Surface Waters of Panhauya Community and Ahmadu Bello University Farm, Zaria

2020 ◽  
Vol 5 (2) ◽  
pp. 138-147
Author(s):  
S. L. Afegbua ◽  
Keyword(s):  
Drinking Water ◽  
Surface Waters ◽  
Water Samples ◽  
Universal Access ◽  
Microbiological Quality ◽  
Health Concern ◽  
Salmonella Spp ◽  
Open Defecation ◽  
E Coli ◽  
Water Borne

The Sustainable Development Goal on sanitation aims to achieve universal access to good health, affordable drinking water, sanitation and an end to open defeacation by 2030. The recent ranking of Nigeria as first globally for open defecation is of public and environmental health concern. This study assessed the sanitary condition and the microbiological quality of well and surface waters of Panhauya community and Ahmadu Bello University farm, Zaria, and the antibiogram of the bacterial isolates.. Based on the WHO criteria, the sanitary inspection showed that 16.7%, 54.2%, 25% and 4.2% of the water sampling points had a very high, high, intermediate and low risk of contamination respectively. Occurrence of Escherichia coli, Giardia lamblia, Entamoeba histolytica, Pseudomonas aeruginosa, Salmonella spp and Vibrio cholerae in water samples from Panhuaya community was 87.5%, 75%, 68.8%, 50%, 25% and 12.5% respectively. In ABU farm Shika, the occurrence was; E. coli (75%), E. histolytica (63%), G. lamblia and Salmonella spp. All E. coli isolates exhibited high multidrug resistance to antibiotics screened with a MAR index of 0.3-0.8. The drinking water sources in Panhuaya and ABU farm were unsafe and the presence of these pathogens in the water samples may be attributed to a number of factors including poor sanitation, manure application and open defecation practice. This indicates a public health risk to the residents and emphasises the need for safe water supplies sanitation and antibiotic stewardship. Keywords: Well water; surface water; sanitary inspection; open defecation; water-borne pathogens; Zaria.

scholarly journals Characterization and Comparative Genomic Analysis of a Novel Bacteriophage, SFP10, Simultaneously Inhibiting both Salmonella enterica and Escherichia coli O157:H7

2011 ◽  
Vol 78 (1) ◽  
pp. 58-69 ◽  
Author(s):  
Minjung Park ◽  
Ju-Hoon Lee ◽  
Hakdong Shin ◽  
Minsik Kim ◽  
Jeongjoon Choi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Salmonella Enterica ◽  
Burst Size ◽  
Genomic Analysis ◽  
Comparative Genomic ◽  
Tail Fiber ◽  
Content Type ◽  
E Coli ◽  
Development Of Resistance

ABSTRACTSalmonella entericaandEscherichia coliO157:H7 are major food-borne pathogens causing serious illness. Phage SFP10, which revealed effective infection of bothS. entericaandE. coliO157:H7, was isolated and characterized. SFP10 contains a 158-kb double-stranded DNA genome belonging to the Vi01 phage-like familyMyoviridae.In vitroadsorption assays showed that the adsorption constant rates to bothSalmonella entericaserovar Typhimurium andE. coliO157:H7 were 2.50 × 10−8ml/min and 1.91 × 10−8ml/min, respectively. One-step growth analysis revealed that SFP10 has a shorter latent period (25 min) and a larger burst size (>200 PFU) than ordinaryMyoviridaephages, suggesting effective host infection and lytic activity. However, differential development of resistance to SFP10 inS.Typhimurium andE. coliO157:H7 was observed; bacteriophage-insensitive mutant (BIM) frequencies of 1.19 × 10−2CFU/ml forS.Typhimurium and 4.58 × 10−5CFU/ml forE. coliO157:H7 were found, indicating that SFP10 should be active and stable for control ofE. coliO157:H7 with minimal emergence of SFP10-resistant pathogens but may not be forS.Typhimurium. Specific mutation ofrfaLinS.Typhimurium andE. coliO157:H7 revealed the O antigen as an SFP10 receptor for both bacteria. Genome sequence analysis of SFP10 and its comparative analysis with homologousSalmonellaVi01 andShigellaphiSboM-AG3 phages revealed that their tail fiber and tail spike genes share low sequence identity, implying that the genes are major host specificity determinants. This is the first report identifying specific infection and inhibition ofSalmonellaTyphimurium andE. coliO157:H7 by a single bacteriophage.

scholarly journals Biological Characteristics and Genomic Analysis of Aeromonas Hydrophila Phage BUCT551 Isolated From Aquatic Sewage

2021 ◽  
Author(s):  
Hongbo Qin ◽  
Shiting He ◽  
Xuling Xu ◽  
Xiaoping An ◽  
Ke Liu ◽  
...  
Keyword(s):  
Aeromonas Hydrophila ◽  
Burst Size ◽  
Genomic Analysis ◽  
Opportunistic Pathogen ◽  
Range Analysis ◽  
Transmission Electron ◽  
Blastn Analysis ◽  
One Step ◽  
Ph Range ◽  
The One

Abstract Aeromonas hydrophila is a common opportunistic pathogen in aquaculture and is ubiquitous in aquatic environment. Whereby its accessibility, variety and host specificity, phage is increasingly considered as a promising complementary medicine for antibiotics. However, a small amount of A. hydrophila phages have been characterized, which suggests the significance to isolate and characterize novel A. hydrophila phages. In this study, we isolated a novel Aeromonas hydrophila phage using A. hydrophila strain A18 as an indicator and designated it as BUCT551, and it was identified as Myoviridae phage by transmission electron microscopy (TEM). The whole genome sequencing of the phage BUCT551 revealed that it has a linear DNA genome of 613,82 bp. BLASTn analysis showed that phage BUCT551 shared 86.75% homology with A. hydrophila phage LAh_7 (Genebank ID: MK838113.1). The one-step growth curve demonstrated that phage BUCT551 had a latent period of 20 min and the burst size of 32 pfu/cell at its optimal MOI of 0.1. The phage BUCT551 had a survival pH range from 5 to 10 and tolerant temperature from 0℃ to 40℃. Host range analysis shown that the phage was able to lyse not only A. hydrophila, but also A. veronii.

scholarly journals Preponderance of blaKPC-Carrying Carbapenem-Resistant Enterobacterales Among Fecal Isolates From Community Food Handlers in Kuwait

2021 ◽  
Vol 12 ◽  
Author(s):  
Ola H. Moghnia ◽  
Vincent O. Rotimi ◽  
Noura A. Al-Sweih
Keyword(s):  
Health Concern ◽  
Food Handlers ◽  
Gene Characterization ◽  
E Coli ◽  
Carbapenem Resistant ◽  
Significant Public Health Concern ◽  
The Family ◽  
Significant Public Health ◽  
Molecular Mode ◽  
Sequence Types

Carbapenem-resistant Enterobacterales (CRE) are pathogens that have been found in several countries, with a significant public health concern. Characterizing the mode of resistance and determining the prevailing clones are vital to the epidemiology of CRE in our community. This study was conducted to characterize the molecular mode of resistance and to determine the clonality of the CRE fecal isolates among community food handlers (FHs) vs. infected control patients (ICPs) in Kuwait. Fecal CRE isolates obtained from FHs and ICPs from September 2016 to September 2018 were analyzed for their resistance genes. Gene characterization was carried out by polymerase chain reaction (PCR) assays and sequencing. Clonality of isolates was established by multilocus sequence typing (MLST). Of the 681 and 95 isolates of the family Enterobacterales isolated from FHs and ICPs, 425 (62.4%) and 16 (16.8%) were Escherichia coli, and 18 (2.6%) and 69 (72.6%) were Klebsiella pneumoniae, respectively. A total of 36 isolates were CRE with a prevalence of 5.3% among FH isolates and 87 (91.6%) among the ICPs. Of these, carbapenemase genes were detected in 22 (61.1%) and 65 (74.7%) isolates, respectively (p < 0.05). The detected specific genes among FHs and ICPs were positive for blaKPC 19 (86.4%) and 35 (40.2%), and blaOXA 10 (45.5%) and 59 (67.8%), in addition to blaNDM 2 (9.1%) and 32 (36.8%), respectively. MLST assays of the E. coli and K. pneumoniae isolates revealed considerable genetic diversity and polyclonality as well as demonstrated multiple known ST types and eight novel sequence types. The study revealed a relatively high number of CRE harboring predominantly blaKPC-mediated CRE among the community FH isolates vs. predominant blaOXA genes among the ICPs. Those heterogeneous CRE isolates raise concerns and mandate more efforts toward molecular surveillance. A multinational study is recommended to monitor the spread of genes mediating CRE in the community of Arabian Peninsula countries.

scholarly journals Bacterial Composition of Biofilms of a Local Tigernut Drink Processing Unit in Yenagoa, Nigeria

2021 ◽  
Vol 4 (2) ◽  
pp. 59-70
Author(s):  
Juliana O.P. ◽  
Adenike B.A.
Keyword(s):  
Bacterial Load ◽  
Water Storage ◽  
Health Concern ◽  
Processing Unit ◽  
Open Market ◽  
Salmonella Spp ◽  
E Coli ◽  
Significant Difference ◽  
Sampling Points ◽  
Storage Containers

Microorganisms grow and form biofilms on surfaces of equipment employed in food processing. These biofilms are considered as the major sources of contamination in the food industry. The study determined the bacterial load and composition on surfaces of equipment and utensils employed in tigernut drink production, from a vendor with a production unit located in an open market in Yenagoa, Nigeria. Swabs were taken from different sampling points made of varying materials—the grinding machine (metal), the collection bowls, water storage containers (thick plastic) and retail bottles (light plastic). These were analysed for total heterotrophic bacterial counts (THBC) and bacterial diversity using standard procedures. The THBC of water used in the drink production was also determined. The THBC of the sampling points ranged from log 3.28±0.06 cfu/cm2 to log 5.18±0.05 cfu/cm2, and log 5.13±0.07 cfu/ml for the water sample. The grinder and water recorded higher bacterial load with a statistically significant difference (P<0.05). The retail bottles had the least bacterial count. Shigella spp. were the most isolated (27.451%), then Salmonella spp. (21.568%) and E. coli (15.686%). Streptococcus spp., Staphylococcus spp. and Vibrio spp. were the least isolated (11.765% each). Shigella and Salmonella species occurred at all sampling points but not on the retail bottles. E. coli was present in the water collection bowls and retail bottles while Streptococcus, Staphylococcus and Vibrio were found only in the retail bottles. On diversity, four bacterial genera (39.216%) were isolated from the retail bottles, three (25.490%) from the water storage containers and two (17.647%) from the grinder and collection bowls. The microorganisms possibly had preference for attachment to the surfaces based on the material makeup and nutrient availability. Their occurrence and high numbers reflect the low level of hygiene employed prior to drink production. This could be of public health concern.

scholarly journals Multidrug Resistant CTX-M-ProducingEscherichia coli: A Growing Threat among HIV Patients in India

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Kesavaram Padmavathy ◽  
Krishnan Padma ◽  
Sikhamani Rajasekaran
Keyword(s):  
Multidrug Resistance ◽  
Multidrug Resistant ◽  
Health Concern ◽  
Hiv Patients ◽  
E Coli ◽  
Significant Public Health Concern ◽  
Significant Public Health ◽  
Third Generation Cephalosporins ◽  
Highly Virulent ◽  
Esbl Producers

Extended Spectrumβ-Lactamases (ESBLs) confer resistance to third-generation cephalosporins and CTX-M types have emerged as the most prominent ESBLs worldwide. This study was designed to determine the prevalence of CTX-M positive ESBL-producing urinaryE. coliisolates from HIV patients and to establish the association of multidrug resistance, phylogeny, and virulence profile with CTX-M production. A total of 57 ESBL producers identified among 76E. colistrains isolated from HIV patients from South India were screened forblaCTX-M, AmpC production, multidrug resistance, and nine virulence associated genes (VAGs),fimH,pap,afa/dra,sfa/foc,iutA,fyuA,iroN,usp,andkpsMII.The majority (70.2%) of the ESBL producers harboredblaCTX-Mand were AmpC coproducers. Among the CTX-M producers, 47.5% were found to be UPEC, 10% harbored as many as 7 VAGs, and 45% possessedkpsMII. Multidrug resistance (CIPRSXTRGENR) was significantly more common among the CTX-M producers compared to the nonproducers (70% versus 41.2%). However, 71.4% of the multidrug resistant CTX-M producers exhibited susceptibility to nitrofurantoin thereby making it an effective alternative to cephalosporins/fluoroquinolones. The emergence of CTX-M-producing highly virulent, multidrug resistant uropathogenicE. coliis of significant public health concern in countries like India with a high burden of HIV/AIDS.

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