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.

High levels of toxigenic Clostridioides difficile contamination of hospital environments: a hidden threat in hospital-acquired infections in Kenya

Introduction. The contribution of Clostridioides difficile (formerly Clostridium difficile ) to the burden of hospital-associated infections (HAIs) remains undetermined in many African countries. Aim. This study aimed to identify a sensitive and readily adaptable C. difficile detection assay and to evaluate the C. difficile HAI risk in Kenya. Methodology. Sterile swabs in neutralizing buffer were used to sample equipment or surfaces that patients and clinical staff touched frequently. These swabs were either plated directly on chromogenic agar or cultured in an enrichment broth before plating. The swab suspensions, enrichment broth and plate cultures were screened by quantitative PCR (qPCR) to determine the most efficient detection method. The HAI risk was evaluated by testing the C. difficile -positive samples by qPCR for the A, B and binary toxins. Results. C. difficile was detected on 4/57 (7.0 %) equipment and surfaces by direct culture. The additional enrichment step increased the detection rate 10-fold to 43/57 (75.4 %). In total, 51/57 (89.5 %) environmental samples were positive for C. difficile detected through either culture or qPCR. The genes encoding the primary toxins, tcdA and tcdB, were detected on six surfaces, while the genes encoding the binary toxins, cdtA and cdtB, were detected on 2/57 (3.5 %) and 3/57 (5.3 %) surfaces, respectively. Different C. difficile toxin gene profiles were detected: the tcdA+/tcdB− gene profile on 4/10 (40 %) high-touch surfaces, tcdA−/tcdB+ on 3/10 (30 %) surfaces, tcdA+/tcdB+/cdtA+/cdtB+ on 2/10 (20 %) surfaces and tcdA−/tcdB+/cdtB+ on one high-touch surface. Conclusion. The widespread contamination of hospital environments by toxigenic C. difficile gives a strong indication of the high risk of C. difficile infections (CDIs). The two-step culture process described can easily be adapted for monitoring hospital environment contamination by C. difficile .

Evaluation of Methods of Enrichment and Compositing of Environmental Samples for Detection of Listeria monocytogenes

Various methods exist for the enrichment and detection of Listeria spp. and L. monocytogenes from environmental samples. Procedures for the compositing of environmental samples are not as well-defined. In this study, different enrichment procedures involving Buffered Listeria Enrichment Broth (BLEB), University of Vermont Medium (UVM), and Fraser Broth (FB) were evaluated to determine the limits of detection (LOD) for L. monocytogenes from culture and from swabs of stainless steel and to assess the efficacy of composite sampling by wet (pooling of primary enrichments) and dry (pooling of swabs) procedures. For detection of cells in pure culture, the computed LOD95% values using a single-step BLEB or two-step UVM-FB enrichment were 0.33 and 0.49 CFU per 225 mL enrichment, respectively. No significant differences in detection were observed for procedures using either two-step BLEB-FB or UVM-FB enrichments for swabs of stainless steel when L. monocytogenes was inoculated at 2-6 log CFU; LOD95% values were 3.82 and 3.62 log CFU per 4 in2 area, respectively. Wet compositing of L. monocytogenes from culture with and without Romaine lettuce wash (RLW) resident microbiota was conducted using BLEB-FB and UVM-FB enrichment methods; both allowed detection of the pathogen at ratios of 1:1, 1:2, 1:4 and 1:7 (1 positive : x negative samples) with no loss in sensitivity. From swabs of stainless steel, L. monocytogenes was detected similarly for both wet and dry composites of up to eight samples (1:7) with RLW. However, the BLEB-FB method allowed for significantly faster detection (after 24 h of FB incubation) in composites of 1:4 and 1:7 compared to the UVM-FB method under the conditions tested. The results of this study provide data to evaluate the efficacies of the different enrichment procedures and aid in assessing the use of wet and dry compositing of environmental samples for use in food production and processing facilities as part of a Listeria control plan.