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Ofori, L. A.

Publications and source records attributed to Ofori, L. A..

2 recordsLinked to original sources

BACTERIAL AND FUNGAL CONTAMINATION OF STAIRCASE BANISTERS AT THE COLLEGE OF SCIENCE, KWAME NKRUMAH UNIVERSITY OF SCIENCE AND TECHNOLOGY, GHANA

Staircase banisters are frequently touched surfaces that may receive microorganisms from hands, dust, air and other environmental sources, but their microbial status in Ghanaian university buildings has received limited attention. This cross-sectional environmental microbiology study assessed bacterial and fungal contamination of staircase banisters at the Kwame Nkrumah University of Science and Technology, Kumasi. Six banisters from the Aboagye Menyah Building Complex, Chemistry Block and Biology Block were purposively selected to include high-traffic locations and both wooden and metal surfaces. Upper and lower sections were sampled over three consecutive Monday afternoons after classes, giving 12 surface samples. Approximately 150 cm{superscript 2} of each section was swabbed with sterile buffered peptone water, cultured on standard bacteriological and mycological media, and analysed using phenotypic and morphological methods. Bacterial loads were compared by independent samples t-test. Thirty-one bacterial isolates were recovered. The study found Gram-positive bacteria which accounted for 74% of isolates and Gram-negative bacteria for 26%. Staphylococcus spp., Streptococcus spp., Enterobacteriaceae, Bacillus spp. and Corynebacterium-+ spp. were the main presumptive bacterial groups. Metal banisters had higher mean bacterial loads than wooden banisters (4.38 {+/-} 0.86 versus 1.24 {+/-} 1.44 log10 CFU/mL; p = 0.014), whereas upper and lower sections did not differ significantly (p = 0.539). Fungal growth was detected in all samples, with Aspergillus fumigatus, Colletotrichum spp. and Aspergillus niger being frequent presumptive fungi. The findings support the routine inclusion of staircase banisters in cleaning and disinfection programmes for academic buildings.

microbiology↗

Genomic Insights into the Diversity, Antimicrobial Resistance, and Zoonotic Potential of Campylobacter fetus Across Diverse Hosts and Geographies

BackgroundCampylobacter fetus causes reproductive diseases in livestock and zoonotic infections in humans, especially in immunocompromised individuals. Despite its significance, its genomic characteristics are poorly understood. This study analyzed 114 publicly available C. fetus genomes to provide global insights into its genetic diversity, antimicrobial resistance (AMR) patterns, and zoonotic risk. ResultsA total of 32 distinct sequence types (STs), ranging from ST-1 to ST-74, were identified across 111 of the 114 C. fetus genomes, spanning six continents and diverse hosts (cattle, humans, sheep, and reptiles). ST-4 was the most prevalent (n = 45), followed by ST-3 (n = 8). A significant proportion (90.9%; n/N=40/44) of C. fetus subsp. venerealis (Cfv) and its biovar intermedius (Cfvi) were assigned to ST-4. Despite being isolated from five continents, Cfv and Cfvi genomes clustered closely, forming distinct branches at the biovar level; however, six Cfv genomes were located within Cfvi clades, suggesting a shared evolutionary lineage. In contrast, C. fetus subsp. testudinum (Cft) genomes, exhibiting 20 distinct STs, formed distinct clades from Cfv, Cfvi, and C. fetus subsp. fetus (Cff). While Cfv genomes from North America and Cfvi genomes from South America formed distinct geographic clusters, Cff genomes displayed no clear geographical patterns, with branches containing strains from multiple continents, indicating a globally dispersed distribution. Pangenomic analysis revealed pronounced clustering within Cft, characterized by unique gene presence/absence patterns. Five distinct AMR genes were detected, with tet(O) (n = 3) being the most common. Horizontal gene transfer analysis identified 140 genomic islands across 41 genomes, and virulence factor analysis revealed cheY as the sole conserved virulence gene across 35 genomes. ConclusionThese findings provide critical insights into the genomic diversity, zoonotic potential, and global distribution of C. fetus, emphasizing the need for integrated genomic and epidemiological strategies to assess its impact on human and animal health.

genomics↗