Bangladesh Journal of Microbiology 2021-01-06T10:37:55+00:00 Professor Mahmuda Yasmin Open Journal Systems <p>The official journal of the Bangladesh Society of Microbiologists. Full text articles available</p> Comparison of Immunogenicity and Protective Efficacy of the Intranasal and Intraperitoneal Immunization Routes of <i>Escherichia albertii</i> Strain DM104 in Mouse Model 2021-01-06T10:37:45+00:00 Fatema Moni Chowdhury Nils Kare Birkeland Chowdhury Rafiqul Ahsan <p>In recent years, our group isolated the Escherichia albertii strain DM104 and characterized it as a vaccine strain against Shigella dysenteriae type 4 in the guinea pig eye model. Protective efficacy of different routes of immunization such as intranasal, oral, and intrarectal routes were also determined and compared by challenging immunized guinea pigs against live S. dysenteriae. In the current study, we compared the intranasal and intraperitoneal routes of immunizations with the DM104 vaccine strain in mice to understand the better route of administration of the DM104 vaccine and its immunogenicity as well as protective efficacy in mouse model. The results indicate that the immune response elicited by the DM104 strain is strongly dependent on the immunization route, with the intranasal route being more effective than the intraperitoneal route following intraperitoneal live S. dysenteriae challenge. Intranasal immunization yielded 80% protective efficacy in immunized mice whereas, intraperitoneal immunization could not provide any protection. Protection generated by intranasal immunization was accompanied by high titre of anti-whole cell lysate IgG and IgA in DM104 immunized sera compared to sera collected from mice of control group. All these data demonstrate the intranasal route of the vaccine DM104 strain in mouse model to be a better immunization route to protect the animals against live S. dysenteriae challenge.</p> <p>Bangladesh J Microbiol, Volume 37 Number 2 December 2020, pp 38-41</p> 2020-12-31T00:00:00+00:00 Copyright (c) 2020 Bangladesh Journal of Microbiology Clinical Characteristics of Noncritical Patients with Coronavirus Disease 2019 (COVID-19): Lessons from Bangladesh 2021-01-06T10:37:48+00:00 Md Shahed Morshed Abdullah Al Mosabbir Prodipta Chowdhury Sheikh M Ashadullah Mohammad Sorowar Hossain <p>The scientific literatures on clinical manifestations of coronavirus disease 2019 (COVID-19) patients from South Asian countries including Bangladesh are limited. Documentation of clinical spectrum from various geographic locations is vital for future scientific studies and clinical management. This study is aimed to report the sociodemographic and clinical characteristics of noncritical patients with COVID-19 in Bangladesh. We conducted a cross-sectional study at three dedicated COVID-19 hospitals of Bangladesh. The severity of the COVID-19 cases was assessed based on the WHO interim guidance. Data were collected only from non-critical COVID-19 patients as critical patients required immediate management. A total of 103 real-time polymerase chain reaction (RT-PCR) confirmed noncritical COVID- 19 patients were included. Most of the patients (71.8%) were male. Mild, moderate and severe illness were assessed in 74.76%, 9.71% and 15.53% of patients respectively. Nearly 52.4% patients had a co-morbidity, with hypertension being the most common (34%), followed by diabetes mellitus (21.4%) and ischemic heart disease (9.7%). Fever (78.6%), weakness (68%) and cough (44.7%) were the most common clinical manifestations. Other common symptoms included loss of appetite (37.9%), difficulty in breathing (37.9%), loss of taste or smell (35.0%), headache (32%) and body ache (32%). The median time from onset of the first symptom to attending hospitals was 7 days (interquartile range: 4 - 10). This study will help both the clinicians and epidemiologists to understand the magnitude and clinical spectrum of COVID-19 patients in South Asian perspective including Bangladesh.</p> <p>Bangladesh J Microbiol, Volume 37 Number 2 December 2020, pp 42-46</p> 2020-12-31T00:00:00+00:00 Copyright (c) 2020 Bangladesh Journal of Microbiology Food Safety Knowledge, Attitudes and Behavior of Street Food Vendors and Consumers in Dhaka City 2021-01-06T10:37:50+00:00 Sumaiya Mamun Sabiha Alam Mohammad Abduz Zaher AK Obidul Huq <p>Food safety knowledge, attitudes, and street food suppliers and consumer behaviors of the capital city Dhaka were investigated. A cross-sectional study was conducted using questionnaires based on previous studies. Three main areas addressed in the surveys and statistical analysis are; 1) statistical data including gender, age, education, income, food safety training, and specific elements related to the work experience of suppliers, 2) knowledge of food safety such as the awareness of consumers and suppliers concerning pathogenic microbes that cause food poisoning, food and personal hygiene, proper cleaning procedures and high-risk groups, and 3) list of food handling attitude and behavior of subjects. Results showed food safety knowledge of street vendors in the High-tech Industries Development Zone was the lowest, where education levels are generally relatively low. Food safety attitudes of the youngest consumers were significantly better than those of older age groups. Street vendors were relatively poor in carrying out safe food handling, with only 27.6% using or being fully equipped with hand-washing facilities, although more than 50% of vendors were not wearing clean and tidy clothes and masks. Steps should be taken to improve street food stall operating conditions and facilities, including access of potable water, providing clean protected structures, and efficient waste collection and disposal systems that can promote the plans and strategies to improve street food safety of Dhaka city and Bangladesh as a whole.</p> <p>Bangladesh J Microbiol, Volume 37 Number 2 December 2020, pp 48-51</p> 2020-12-31T00:00:00+00:00 Copyright (c) 2020 Bangladesh Journal of Microbiology Physicochemical Properties of Chitosan Extracted from <i>Pleurotus ostreatus</i> and Improvement of its Antibacterial Activity by Gamma Radiation 2021-01-06T10:37:52+00:00 Md Tanvir Kabir Md Shahinur Kabir Abdul Bathen Miah Md Azadul Kabir Sarker Md Kamruzzaman Pramanik <p>This study was carried out to determine the physicochemical characteristics such as intrinsic viscosity (IV), molecular weight (MW), water binding capacity (WBC), and fat binding capacity (FBC) of chitosan extracted Pleurotus ostreatus fruit body. Antibacterial activity of the gamma irradiated chitosan was also determined. The intrinsic viscosity, MW, WBC and FBC of the produced chitosan were 769.69 ml/g, 1.8×10<sup>5</sup> Da, 408% and 234%, respectively. The fungal chitosan was subjected to different doses (viz., 5, 10, 20, 30 and 40 kGy) of radiation from <sup>60</sup>C<sub>o</sub> gamma source to observe the effect of gamma radiation on its antibacterial activity. After irradiation, antibacterial activity was evaluated and compared with that of non-irradiated chitosan. Non-irradiated chitosan showed moderate antibacterial activity against Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 35150, and Salmonella enteritidis ATCC 13076 whereas chitosan samples treated with 5, 10 and 20 kGy gamma irradiation separately have shown enhanced antibacterial activity than that of non-irradiated chitosan against the above-mentioned bacteria. However, higher doses of gamma irradiation (30 kGy and 40 kGy) caused a gradual decline of the antibacterial activity.</p> <p>Bangladesh J Microbiol, Volume 37 Number 2 December 2020, pp 52-55</p> 2020-12-31T00:00:00+00:00 Copyright (c) 2020 Bangladesh Journal of Microbiology Bacterial Isolates and Antibiotic Sensitivity Pattern from Urinary Tract Infection in a Private Diagnostic Laboratory in Dhaka, Bangladesh 2021-01-06T10:37:53+00:00 Md Habibur Rahman Md Mushtaque Ahmed Dayanidhi Sarkar Md Asadur Rahman <p>Urinary tract infection (UTI) is a common infection encountered by clinicians and despite the widespread availability of antimicrobial agents, UTI has become difficult to treat because of appearance pathogens with increasing resistance to antimicrobial agents. The objectives of this study were to determine the pathogens causing UTI and to determine the antibiotic sensitivity status among these isolates in a diagnostic laboratory in Dhaka city. A laboratory based cross sectional survey was conducted in a diagnostic Centre in Dhaka Bangladesh from July 2016 to December 2016. A total of 553 urine samples were collected from each patients and processed in microbiology laboratory to isolate pathogens and antibiotic susceptibility test using standard procedure. Among 553 urine samples, 158 (28.57%) samples was found to be culture positive of which 39 (24.70%) were isolated from male patients and 119 (75.30%) from female patients. Escherichia coli (43.67%) were found to be the predominant pathogen followed by Staphylococcus spp. (16.45%), Enterococcus spp. (13.39%), Klebsiella spp. (13.29%), Candida spp. (5.70%), Acinetobacter spp. (4.43%), Pseudomonas spp. (3.80%) and Proteus spp. (1.27%). The carbapenem group antibiotics (imipenem and meropenem) was found to be resistant in 0 to 5.1% of the Gram negative isolates. On the Other hand, most of the Gram positive isolates showed sensitivity to linezolid and vancomycin. This study showed that E. coli isolates were the predominant pathogens and showed resistance to commonly prescribed drugs resulting in a very few options for drug to treat UTIs.</p> <p>Bangladesh J Microbiol, Volume 37 Number 2 December 2020, pp 56-60</p> 2020-12-31T00:00:00+00:00 Copyright (c) 2020 Bangladesh Journal of Microbiology Effect of Selected Antibiotics on Biofilm Formed by <i>Salmonella Enterica</i> Serovars Typhi and Paratyphi 2021-01-06T10:37:47+00:00 Israt Jahan Rini Md Ariful Islam Sunjukta Ahsan <p>Salmonella enterica serovars Typhi and Paratyphi are the causative agents of typhoid and paratyphoid, respectively, in human. Salmonella is able to form biofilms whereby members are resistant and persistent in both host and nonhost environments. In the present study the effect of the antibiotics, Azithromycin, Imipenem, Ceftriaxone and Cefixime, on planktonic and biofilm phase clinical isolates of Salmonella enterica serovars Typhi (n = 30) and Paratyphi A (n= 07) was investigated. MIC (Minimum Inhibitory Concentration) and MBC (Minimum Bactericidal Concentration) of planktonic phase bacteria were determined and compared with MRC (Minimum Re-growth Concentration) and MBEC (Minimum Biofilm Eradication Concentration) of biofilm population. The present study indicates that, with the exception of Azithromycin, a considerably higher concentration is needed for all other antibiotics investigated to inhibit growth of test isolates in the biofilm phase. We conclude that the requirement of Azithromycin at sub-MIC concentration to inhibit/kill Salmonella in biofilm is of particular significance in that it can be employed for the eradication of Salmonella spp. biofilms.</p> <p>Bangladesh J Microbiol, Volume 37 Number 2 December 2020, pp 62-65</p> 2020-12-31T00:00:00+00:00 Copyright (c) 2020 Bangladesh Journal of Microbiology