Prevalence and Recovery of Microorganisms from Containers used for the Collection of Forensic Biological Samples

Background: Microbes play a significant role in the degradation of biological evidence collected for forensic analysis. The present study is aimed to isolate and identify the microbes present inside the empty container used for the biological evidence collection. Methods: Bacterial isolation from the selected containers was done by cotton swab over the inner surface of the containers. Streaking was done on the surface of the three different culture plates as a Blood agar plate, Nutrient plate and MacConkey plate. The plates were placed in an incubator shaker at 37ºC for 48 hours. The colonies grown on the surface of the media were counted on and used for further study. Various biochemical assays were performed to characterize isolated bacteria. Results: Staining results suggested that the presence of Gram-positive stain (Staphylococcus, Bacillus, Corynebacterium, Clostridium) and Gram negative stain (E. coli, Enterobacteriaceae, Pseudomonas, Salmonella, Shigella, Stenotrophomonas, Bdellovibrio, Acetic acid bacteria). The Catalase and Coagulase test suggested the presence of Staphylococcus aureus, S. epidermis and S. sapropyticus. Moreover, the indole test suggested the presence of Citrobacter koseri, Kebsiella oxytoca, Proteus vulgaris etc. Some of the bacteria were urea metabolizing, including Proteus spp, Helicobacter pylori, Cryptococcus spp, Corynebacterium spp. Conclusion: This study recommends that there should be proper maintenance of the chain of custody from the collection to analysis so that evidence properly prevents degradation or contamination in the biological evidence. Extra care is needed for the collection and packing of biological evidence from the crime scene. Moreover, the collection containers, if left wide open, lead to contamination and degradation of biological evidence.

Alternative Causes of Infectious Diarrhea in Patients with Negative Tests for Clostridoides Difficile

Background Hospitalized patients with diarrhea who have a negative Clostridoides difficile (C. difficile) test are not routinely evaluated for alternative causes of infectious diarrhea. This study assessed for potential infectious causes of diarrhea in hospitalized patients with an order for repeat C. difficile toxin enzyme immunoassay (tEIA) testing after an initial tEIA test was negative. Methods For patients age ≥18 years who had a second C. difficile tEIA test ordered within 96 h after a negative tEIA test, remnant fecal specimens from the first (negative) tEIA test were evaluated using the BioFire FilmArray Gastrointestinal Panel PCR, C. difficile toxigenic culture, and culture on a blood agar plate (BAP) to identify other potential causes of infectious diarrhea. Growth of organisms on the BAP was also used to assess potential disruptions in the gastrointestinal microbiota. Results Among 84 remnant specimens, toxigenic C. difficile was identified in 9 (11%) by culture or PCR, while potential alternative causes of infectious diarrhea, including norovirus, rotavirus, enteropathogenic Escherichia coli, and Salmonella, were identified in 11 specimens (13%) by PCR. For the majority of patients, no infectious cause of diarrhea was identified, but 84% exhibited disrupted gastrointestinal microbiota, which may contribute to diarrhea. Conclusions When a hospitalized patient has a negative C. difficile tEIA test but continues to have diarrhea, alternative infectious and noninfectious causes of diarrhea should be considered. If the patient has clinical signs and symptoms suggestive of infection or risk factors for gastrointestinal infection, laboratory testing for other etiologic agents may be appropriate.

Potential impact of oral flora dispersal on patients wearing face masks when undergoing ophthalmologic procedures

ObjectiveThe purpose of this study is to investigate the amount of oral flora dispersion towards the ocular surface in relation to various face mask scenarios.Methods and analysisThirty participants were recruited for this prospective cross-sectional study. Each participant was seated and instructed to hold a blood agar plate perpendicular to the bridge of their nose and facing downward. Participants then partook in three unique face mask scenarios: no face mask, surgical face mask and surgical face mask with tape securing the superior edge. During each scenario, participants were instructed to forcefully exhale for 5 s three times. The primary outcome measure was the number of colony-forming units (CFUs) grown on each face mask scenario-specific plate.ResultsThirty participants were recruited for the study, and a total of 90 chocolate agar plates were successfully incubated. The proportion of detecting any CFU was 6.67% (95% CI: 0.818% to 22.1%) for no mask scenario, 0% (95% CI: 0% to 11.6%) for mask scenario and 3.33% (95% CI: 0.0844% to 17.2%) for mask-taped scenario. The mean differences in proportion of detecting any CFU were 3.33% (95% CI: 0% to 10%, p=0.309) for no mask versus mask taped, 3.35% (95% CI: 0% to 10%, p=0.307) for mask taped versus mask and 6.68% (95% CI: 0% to 16.7%, p=0.142) for no mask versus mask.ConclusionThis study showed no difference in bacterial dispersion towards the ocular surface when comparing no face mask, a surgical face mask without tape or a surgical face mask with tape.

UJI AKTIVITAS ANTIBAKTERI EKSTRAK ETANOL DAUN KAYU MANIS (Cinnamomum burmannii blume) TERHADAP PERTUMBUHAN BAKTERI Porphyromonas gingivalis DENGAN METODE DISC DIFFUSION

Periodontitis merupakan penyakit tertinggi keenam di seluruh dunia dengan Porphyromonas gingivalis sebagai salah satu bakteri penyebabnya. Daun kayu manis (Cinnamomum burmannii blume) menunjukkan beberapa aktivitas antimikroba, seperti antibakteri dan anti-jamur. Penelitian ini dilakukan untuk mengetahui aktivitas antibakteri ekstrak Cinnamomum burmannii blume terhadap pertumbuhan Porphyromonas gingivalis. Desain penelitian yang digunakan adalah the post test only control group design. Bakteri Porphyromonas gingivalis ditumbuhkan pada medium Blood Agar Plate (BAP) diberi perlakuan menggunakan ekstrak etanol Cinnamomum burmannii blume dengan konsentrasi sebesar 10%, 20%, 30%, 40%, dan 50%. Pengulangan dilakukan sebanyak 5 kali. Hasil penelitian menunjukkan bahwa ekstrak etanol Cinnamomum burmannii blume tidak membentuk zona hambat di sekitar paper disc terhadap pertumbuhan Porphyromonas gingivalis pada semua konsentrasi. Ekstrak etanol Cinnamomum burmannii blume tidak memiliki aktivitas antibakteri terhadap pertumbuhan Porphyromonas gingivalis

Antimicrobial effects of an organosilane-based disinfectant

Organosilane-based disinfectants have been purported to impart lasting antimicrobial properties when applied to a surface. The implications being dramatic reduction in pathogen transmission via fomites and therefore of great public health importance as a means to limit the spread of outbreaks such as COVID-19. We conducted experiments in our laboratory to assess the efficacy of one such product, which reported anti-microbial protection of up to 120 days, as an operational report for our hospital. 1) The organosilane product was applied on a Mueller Hinton agar plate and left overnight underneath an airconditioned vent to promote mould growth. 2) The organosilane product was applied on a Blood Agar Plate (BAP) that was inoculated with E. Coli and observed over 24 hours. 3) Lastly, the organosilane coating was applied onto plastic plates to simulate hospital ward surfaces. Simulated pathogens (suspension of oral commensals) were spread across the plastic plates, swabbed at 1 hour, 8 hours and 24 hours and then incubated for 24 hours. In all 3 experiments, there was no significant difference in microbial growth between the control and intervention arms. Although our experiments did not assess different methods of application nor effect on different materials applied, the lack of demonstrable effects of the organosilane product calls for caution against widespread use of a product whose claims are unverified.

Potential Pathogenicity of Candida Species Isolated from Oral Cavity of Patients with Diabetes Mellitus

Introduction. In the recent decade, the increased immunocompromised population such as diabetic patients makes a high incidence of invasive Candida infections. Diabetes mellitus is the most common endocrine metabolic disorder, and diabetic patients are more susceptible to oral candidiasis infection. Candidiasis is an opportunistic fungal infection caused by many species of Candida. Secretion of exoenzymes plays an important role in the virulence and pathogenesis of Candida species. The aim of this study was to evaluate the potential role of phospholipase, esterase, and hemolytic activity of Candida species isolated from oral cavity lesions of diabetic patients. Methods. A total of 108 Candida species including 75 Candida albicans and 33 non-Candida albicans species were recovered from the oral cavity of diabetic patients included in our study. Egg yolk agar, Tween 80 opacity medium, and blood agar plate assays were used for determining phospholipase, esterase, and hemolytic activities, respectively. Results. Candida albicans species had the most exoenzyme activity in comparison to non-albicans isolates. Candida albicans isolates showed 97.3%, 100%, and 77.3% phospholipase, hemolysin, and esterase activities, respectively. The difference between Candida albicans and non-Candida albicans was significant in phospholipase ( P < 0.001 ) and hemolytic activity ( P = 0.027 ), but not significant in esterase activity ( P = 0.076 ). Conclusion. This study showed that most of the isolates had different enzymatic patterns, and Candida albicans isolates had the most exoenzyme activity. So due to the potential effects of these enzymes in pathogenesis and virulence effects of Candida species, we can conclude that the severity of extracellular enzymes may play a role in the severity of signs and symptoms of Candida oral cavity infections in diabetic patients.

Diagnostic Performance of Various Methodologies for Group B Streptococcus Screening in Pregnant Woman in China

Maternal vaginal/rectal colonization of group B streptococcus (GBS) is a main risk for neonatal invasive infection. Efficient determination of GBS colonization in pregnant women is crucial. This study aimed to investigate the prevalence of GBS carriage and evaluate the diagnostic performance of six methodologies for GBS screening conducted in China, including blood agar plate, liquid chromogenic medium, and loop-mediated isothermal amplification (LAMP) without pre-enrichment, chromogenic agar plate with pre-enrichment, and GBS antigen detection without and with pre-enrichment in comparison with the standard reference method (Lim broth-enriched subculture with plating on 5% sheep blood agar). Vaginal/rectal swabs were collected from 1,281 pregnant women at 35–37 weeks of gestation. Of them, 309 were taken in triplicate, one for Lim broth-enriched subculture, one for blood agar plate, and the third for GBS antigen detection (Reagent W); 177 were acquired in duplicate, one for Lim broth-enriched subculture and the other for GBS antigen detection (Reagent H); 502 were obtained in duplicate, one for Lim broth-enriched subculture and the other for liquid chromogenic medium; 158 were collected in duplicate, one for Lim broth-enriched subculture and the other for LAMP; and 135 were inoculated in Lim broth-enriched for GBS antigen detection (Reagent W) and subculture with chromogenic agar plate and 5% blood agar plate. The overall prevalence of GBS carriage was 10.1% (130/1,281, 95% CI: 8.5–12.1%) according to the standard reference method. Compared with the standard reference method, the LAMP had excellent performance of sensitivity (100%, 95%CI: 83.4–100%), specificity (94%, 95%CI: 88.1–97.1%), and Yoden index (0.940); as well as the blood agar plate with sensitivity (81.5%, 95%CI: 61.3–93.0%), specificity (100%, 95%CI: 98.3–100.0%), and Yoden index (0.815). The other four methods were not sufficient to reach the threshold in terms of sensitivity or specificity compared to the standard reference method. Furthermore, for LAMP, results can be obtained within 0.5–1 h, while for blood agar plate, which needed 24–48 h, and further identification was required. Our data suggested that the performance of LAMP was highly comparable to the standard Lim broth-enriched subculture and LAMP is considered as an alternative for fast and accurate GBS screening.

A quasi-experimental study on stethoscopes contamination with multidrug-resistant bacteria: Its role as a vehicle of transmission

Stethoscopes have been suggested to be a possible vector of contact transmission. However, only a few studies have focused on the prevalence of contamination by multidrug-resistant (MDR) bacteria and effectiveness of disinfection training to reduce. This study is to investigate the burden of stethoscope contamination with nosocomial pathogens and multidrug-resistant (MDR) bacteria and to analyze habit changes in disinfection of stethoscopes among healthcare workers (HCWs) before and after education and training. We performed a prospective pre and post quasi-experimental study. A total of 100 HCWs (55 doctors and 45 nurses) were recruited. HCWs were surveyed on their disinfection behavior and stethoscopes were cultured by pressing the diaphragm directly onto a blood agar plate before and after education on disinfection. Pulsed-field gel electrophoresis was performed to determine the relatedness of carbapenem-resistant Enterobacteriaceae. Most of the stethoscopes were contaminated with microorganisms before and after the intervention (97.9% and 91.5%, respectively). The contamination rate of stethoscopes with nosocomial pathogens before and after education was 20.8% and 19.2%, respectively. Stethoscope disinfection habits improved (55.1% vs 31.0%; p<0.001), and the overall bacterial loads of contamination were reduced (median colony-forming units, 15 vs 10; p = 0.019) after the intervention. However, the contamination rate by nosocomial pathogens and MDR bacteria did not decrease significantly. A carbapenemase-producing Klebsiella pneumoniae isolates from a stethoscope was closely related to isolates from the patients admitted at the same ward where the stethoscope was used. Stethoscopes were contaminated with various nosocomial pathogens including MDR bacteria and might act as a vehicle of MDR bacteria. Continuous, consistent education and training should be provided to HCWs using multifaceted approach to reduce the nosocomial transmission via stethoscopes.

STERILISASI ALAT KEDOKTERAN GIGI DENGAN STERILISATOR (DRY HEAT) DAN TEKNIK BOILING

Sterilisasi alat kedokteran gigi merupakan hal yang sangat penting untuk menghindari infeksi silang. Penelitian ini bertujuan untuk melihat efektifitas sterilisasi alat kedokteran gigi dengan dry heat sterilitator dan teknik boiling. Metode: sampel penelitian ini adalah kaca mulut yang telah digunakan untuk praktikum klinik. Pengambilan sampel menggunakan teknik accidental sampling dengan jumlah sampel 20 buah. Kaca mulut sebelum dan sesudah disterilkan, ditempelkan pada Blood Agar Plate (BAP) kemudian diinkubasi selama 1 x 24 jam. Hasil: Uji Wilcoxon menunjukkan penurunan jumlah bakteri yang siginifikan pada dry heat sterilisator (P<0,005) sedangkan pada teknik boiling tidak signifikan (P>0,005). Kesimpulan: Dry heat sterilisator lebih efektif dalam mengurangi bakteri pada instrumen dibandingkan teknik boiling.

An initial survey on the prevalence of group B Streptococcus (GBS) among Yemeni pregnant women.

Background: Neonatal infection with group B Streptococcus (GBS) is still a threat to the life of fetus and mother, especially in developing countries that do not adopt a prenatal screening test policy such as Yemen. Objective: This study aimed to determine the vaginal colonization rates and antibiotic susceptibility pattern of group B Streptococcus among pregnant Yemeni women. Methods: We conducted a cross-sectional study over a four-month period involved 210 pregnant women who visited Gaza medical center (a primary health center in Sana’a city, Yemen) at the 35th to 39th gestational weeks. A vaginal swab from each pregnant woman was inoculated in Todd-Hewitt enrichment broth and after 24h incubation; the subculture on a 5% human blood agar plate was performed from inoculated Todd-Hewitt enrichment broth. All positive cultures identified as group B streptococcus were subjected to antibiotic susceptibility test using the disk-diffusion method. Results: Out of 210 recruited pregnant women, 23 (10.95%) were GBS vaginal carriers. All isolates showed no resistance to penicillin, ampicillin, levofloxacin, cefotaxime, and vancomycin. However, we observed decreased sensitivity to clindamycin (82.8%) and tetracycline (30.5%). Conclusion: Based on the study results; approximately eleven out of every 100 pregnant women were vaginal colonized by GBS in Sana'a governorate. Beta-lactam antibiotics remain the drug of choice for treatment and prophylaxis of GBS infections. Therefore, we recommend implementing a screening policy to detect GBS in Yemeni pregnant women.