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Research Article
High Prevalence of Virulence Genes and in Vitro Biofilm Production in Clinical Multidrug-Resistant Escherichia coli in Dakar Senegal
Komla Mawunyo Dossouvi,
Bissoume Sambe Ba,
Gora Lo,
Issa Ndiaye,
Awa Ba-Diallo,
Ousmane Sow,
Assane Dieng,
Fatimata Talla,
Abdoulaye Cissé,
Serigne Mbaye Lo Ndiaye,
Alioune Tine,
Farba Karam,
Habsa Diagne-Samb,
Safietou Ngom-Cisse,
Halimatou Diop-Ndiaye,
Issaka Maman,
Coumba Toure-Kane,
Aïssatou Gaye-Diallo,
Sika Dossim,
Souleymane Mboup,
Cheikh Saad Bouh Boye,
Abdoulaye Seck,
Makhtar Camara
Issue:
Volume 8, Issue 4, December 2023
Pages:
69-81
Received:
28 September 2023
Accepted:
20 October 2023
Published:
31 October 2023
Abstract: Bacterial virulence is a key factor determining the outcome of each bacterial infection, and virulent bacteria are often associated with high-risk infections. Thus, this study aimed to screen for virulence genes and evaluate the in vitro biofilm formation capacity of multidrug-resistant Escherichia coli isolated in Dakar. For the 16 virulence genes identified by standard polymerase chain reaction (PCR), all 78 ExPEC isolates carried at least four virulence genes. The prevalence of virulence genes was as follows: adhesin genes fimH (98.7%), mrkD (98.7%), papC (46.2%), afaC (9%), and sfa/focDE (1.3%); iron acquisition system genes entB (98.7%), fepA (98.7%), ybtS (93.6%), fyuA (91%), iucA (91%), iucB (91%), iutA (34.6), iroB (6.4%), iroN (6.4%), and toxin genes hlyA (10.3%) and cnf (1 & 2) (10.3%). Seventy-five of the 78 isolates (96.2%) carried at least two adhesin genes and two iron capture system genes. Evaluation of the biofilm formation capacity revealed that all (29/29) hospital-acquired isolates were biofilm producers with (6/29; 20.7%) strong biofilm producers, (15/29; 51.7%) moderate biofilm producers and (8/29; 27.6%) weak biofilm producers. Hospital-acquired isolates carrying papC had a greater biofilm formation capacity than those lacking papC (p < 0.001). The deepening of this type of study on bacterial virulence and hospital bacterial biofilms could lead to improvements in infection investigation, prevention, and therapeutic protocols.
Abstract: Bacterial virulence is a key factor determining the outcome of each bacterial infection, and virulent bacteria are often associated with high-risk infections. Thus, this study aimed to screen for virulence genes and evaluate the in vitro biofilm formation capacity of multidrug-resistant Escherichia coli isolated in Dakar. For the 16 virulence genes...
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Research Article
Quantitative Risk Assessment of Campylobacter in Whole Chicken During Retail in Changchun Region
Zhang Weiyu,
Huang Xin,
Nie Dandan,
Yao Jiatong,
Zhang Lifu,
Liu Guihua,
Sui Dawei*
Issue:
Volume 8, Issue 4, December 2023
Pages:
82-86
Received:
24 September 2023
Accepted:
16 October 2023
Published:
9 November 2023
Abstract: Objective: In order to effectively prevent and control diseases caused by Campylobacter, we aim to understand the horizontal distribution and quantitative pollution of Campylobacter species in the retail process of broiler chickens in Changchun area, and provide data basis for quantitative risk assessment of Campylobacter pollution in the retail process of broiler chickens. Methods A total of 240 fresh and refrigerated whole chickens were collected from large supermarkets and farmers' markets around Changchun City. Using plate counting method for bacterial isolation and cultivation, and multiplex PCR method for typing and identification of Campylobacter. Results: A total of 26 positive samples were detected from 240 specimens, with the detection rate of 10.8%. The detection rate of samples, which contamination quantity of Campylobacter was more than 500 cfu/g, reached 2.1% (5 /240). The positive rate of samples in the farmers markets was higher than that in the supermarkets. Conclusion This study investigated the contamination level of Campylobacter during the retail process of whole chickens in Changchun area, providing data support for the risk assessment of Campylobacter contamination in chickens. Remind government regulatory authorities to strengthen the hygiene supervision of live poultry slaughterhouses in the agricultural product market, and improve the risk assessment of Campylobacter in the field of food safety.
Abstract: Objective: In order to effectively prevent and control diseases caused by Campylobacter, we aim to understand the horizontal distribution and quantitative pollution of Campylobacter species in the retail process of broiler chickens in Changchun area, and provide data basis for quantitative risk assessment of Campylobacter pollution in the retail pr...
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Research Article
Detection of Bacteria Contaminating Milk and Milk Products in Tanzania by Conventional and Rapid Methods
Irene Mfilinge*,
Elisa Mwega,
Lucy Chove,
George Msalya
Issue:
Volume 8, Issue 4, December 2023
Pages:
87-93
Received:
4 October 2023
Accepted:
2 November 2023
Published:
17 November 2023
Abstract: The aim of the present study was to evaluate the performance of rapid methods for identifying contaminating bacteria in milk and milk products in Tanzania. A total of 60 milk and milk product samples were collected along the dairy value chain in Morogoro Municipality. The samples included raw and boiled milk, local fermented milk, and industrial processed milk products. Laboratory analyses were conducted using the conventional tests (culture and confirmatory tests) as well as rapid methods (3M petrifilm plate and polymerase chain reaction (PCR). Total bacteria count and identification of Escherichia coli as well as Staphylococcus aureus were performed. Results had indicated that there is positive correlation (R=1) between the 3M petrifilm and conventional methods. On the other hand, the correlation between PCR and the conventional method was poor (R=-0.078 and -0.15 for E. coli and S. aureus identification respectively). Furthermore, the PCR identified more positive samples (8 for E. coli and 12 for S. aureus) compared to the conventional method (2 for E. coli and 5 for S. aureus). No significant difference (p˂0.05) was observed between 3M petrifilm and the conventional methods in tested boiled milk, local fermented milk, and industrial processed milk products; however, significant differences (p˃0.05) were observed in raw milk by both methods. Based on these results and the time to obtain them, it is confirmed that rapid methods performed better than the conventional methods for determining contamination and identifying bacteria in milk and milk products and are hence recommended for routine laboratory analysis in Tanzania.
Abstract: The aim of the present study was to evaluate the performance of rapid methods for identifying contaminating bacteria in milk and milk products in Tanzania. A total of 60 milk and milk product samples were collected along the dairy value chain in Morogoro Municipality. The samples included raw and boiled milk, local fermented milk, and industrial pr...
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Research Article
Epidemiology of Syphilis Among Blood Donors in Brazzaville, Republic of Congo
Brunel Monic Angounda*,
Serge Oscar Mokono,
Felix Koukouikila-Koussounda,
Inatan Systeme Lekanga,
Geneviève Mbanzoulou Boukatou,
Fabien Roch Niama,
Alain Vouidibio
Issue:
Volume 8, Issue 4, December 2023
Pages:
94-97
Received:
2 November 2023
Accepted:
27 November 2023
Published:
6 December 2023
Abstract: Syphilis is a bacterial infection caused by Treponema pallidum and its transmission through blood transfusion poses a considerable risk to transfusion safety. The aim of this study was to assess the prevalence of syphilis among blood donors in Brazzaville, Republic of Congo. This was a cross sectional study conducted from September 2022 to February 2023. Data were collected from the national blood bank in Brazzaville. A structured questionnaire was designed and presented to each donor at the time of sample collection. The demographic data, including age, gender, educational, occupation, marital status and types of donors were routinely collected. During the donation procedure, 5 mL of peripheral blood was collected in a sterile EDTA test tube. All the donor samples were screened by ELISA test. Out of the 2560 blood donors included, 2258 donors (88.2%) were males while 302 (11.8%) were females. The mean age was 32±8.62 years. The overall prevalence of syphilis antibodies was 18 (0.7%). Majority of positive donors were females and in the age group 45-65 years, with a statistically significant correlation (p<0.05). Although, we found a high rate of syphilis carriage among donors in secondary education level, laborer, single and replacement donors, no significant relationship was found (p>0.05). This study provides crucial information on the epidemiology of syphilis among blood donors in Brazzaville and underscores the importance of strengthening screening and prevention strategies among this population.
Abstract: Syphilis is a bacterial infection caused by Treponema pallidum and its transmission through blood transfusion poses a considerable risk to transfusion safety. The aim of this study was to assess the prevalence of syphilis among blood donors in Brazzaville, Republic of Congo. This was a cross sectional study conducted from September 2022 to February...
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Research Article
Microbiological Quality of Rabbit Fish (Signus Sutor) and Food Safety Practice of Fish Handlers from Selected Landing Sites in Zanzibar
Zeyana Nassor Mohamed*,
Abdulsudi Issa-Zacharia,
Frida Nyamete
Issue:
Volume 8, Issue 4, December 2023
Pages:
98-109
Received:
11 November 2023
Accepted:
29 November 2023
Published:
11 December 2023
Abstract: The study aimed to evaluate the handling practices and microbiological contamination of pathogenic bacteria in Rabbit Fish (Signus Sutor) from Zanzibar, specifically at four landing sites: Malindi, Mazizini, Kizimkazi, and Matemwe. A semi-structured questionnaire and checklist were used to assess hygiene practices by fish handlers, and swabbing method was used to assess cleanliness of the boat and landing floor before fish were collected for consumption. Standard methods for microbial analysis (ISO7218:2007(E)) were used to analyze Total viable counts, S. aureus, E. coli, and Salmonella. The mean total viable (TVC) ranged from 2.82-3.30 log CFU/g across landing sites. S. aureus was the most frequently isolated bacterium, with an isolation rate of 53.33% in Malindi, 60% in both Mazizini and Kizimkazi, and 46.67% in Matemwe. E. coli was present but less frequently, with isolation rates of 6.67% in Malindi, 33.33% in Mazizini and Kizimkazi, and 20% in Matemwe. Salmonella spp was absent in all samples, with a 0% isolation rate across landing sites. There was positive correlation of 0.59 and 0.65 between fish contamination and swab samples from boats and landing floors respectively. Inadequate practices by fish handlers, such as not wearing gloves, neglecting health checks, and insufficient training, were revealed. The facilities used were also poor, with poor sanitation and low-quality raw materials. The findings emphasize the urgent need for intervention measures to enhance fish quality and safety in Zanzibar, including improvements in raw materials, infrastructure, training, and good practices throughout the fish value chain.
Abstract: The study aimed to evaluate the handling practices and microbiological contamination of pathogenic bacteria in Rabbit Fish (Signus Sutor) from Zanzibar, specifically at four landing sites: Malindi, Mazizini, Kizimkazi, and Matemwe. A semi-structured questionnaire and checklist were used to assess hygiene practices by fish handlers, and swabbing met...
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Review Article
Microbial Inactivation Mechanism and Properties of Slightly Acidic Electrolyzed Water: A Review
Issue:
Volume 8, Issue 4, December 2023
Pages:
110-121
Received:
9 November 2023
Accepted:
4 December 2023
Published:
18 December 2023
Abstract: Slightly acidic electrolyzed water (SAEW) obtained by electrolyzing 2-6% dilute hydrochloric acid in a chamber without membrane is novel non-thermal sanitizer widely used in the sterilization of foods such as fruits, vegetables, and meat owing to its effective antibacterial activity and low operating costs. Despite the well-documented and validated antimicrobial and sporicidal properties of SAEW, its precise mode of action against bacteria and bacterial spores remains uncertain and subject to ongoing debate. The primary aim of this review article is to scrutinise the active constituents of SAEW that contribute to its antimicrobial properties. Additionally, the review critically elucidates the mechanisms by which SAEW effectively inactivate vegetative bacteria cells and spores, based on a comprehensive scrutiny of existing literature. It is demonstrated that the application of SAEW can kill vegetative bacterial cells by the disruption of their cellular membrane, disruption of their intracellular reactive oxygen species (ROS) balance, and lowering their ATP levels, deactivation of key enzyme and damaging DNA affecting other bacterial cells vitals. Bacterial spore inactivation by SAEW being achieved through the induction of structural modifications in the spores, including coat damage, mutagenesis, and alterations in the properties of the inner membrane (IM).
Abstract: Slightly acidic electrolyzed water (SAEW) obtained by electrolyzing 2-6% dilute hydrochloric acid in a chamber without membrane is novel non-thermal sanitizer widely used in the sterilization of foods such as fruits, vegetables, and meat owing to its effective antibacterial activity and low operating costs. Despite the well-documented and validated...
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