A. DUNKWU-OKAFOR

Antimicrobial resistance (AMR) poses a significant public health threat, enabling bacterial strains to withstand common antimicrobial therapies. This study aimed to determine the prevalence and antibiotic resistance patterns of hospital-acquired Escherichia coli infections among children admitted to a tertiary hospital in Benin City, Nigeria. This was a cross-sectional study conducted from August to October 2025. A total of 80 swab samples were processed using standard culture-based methods. Bacterial isolates were identified via cultural characteristics, Gram staining, and standard biochemical tests (Catalase, Oxidase, Citrate, Indole, VogesProskauer, Hydrogen Sulphide, Methyl red, Urease and Sugar Fermentation). Antimicrobial susceptibility testing (AST) was performed using the Kirby-Bauer disc diffusion method. The antibiotics tested included ceftriaxone, ceftazidime, ciprofloxacin, gentamicin, amoxicillin-clavulanic acid and meropenem. The Patient demographics showed a clear difference, with the highest number recorded among male in-hospital patients (44) and the lowest among female community patients (4). Organism distribution varied by sample site, where Escherichia coli was the dominant isolate in rectal samples (17 isolates). Testing against a panel of 19 antibiotics revealed that most E. coli isolates remained susceptible. The highest resistance was observed against sulfamethoxazole-trimethoprim (7 isolates). Multidrug resistance patterns were diverse, with the combination of ciprofloxacin, piperacillin, and sulfamethoxazole (CIP, PIP, SUL) being the most frequently observed MDR profile (in 2 isolates). These findings align with previous reports from Nigerian hospitals, emphasizing the need for improved antimicrobial stewardship, routine resistance monitoring, and strict infection prevention measures to reduce hospital-acquired infections and ensure effective patient care.

Antimicrobial resistance is mainly caused by the overuse, underuse or misuse of antimicrobials. Antimicrobial resistance (AMR) is defined as a microorganism's resistance to an antimicrobial drug that was once able to treat an infection by that microorganism The present study was designed to assess the prevalence of MRSA among outpatients presenting Evboutubu primary health center, Egor LGA Benin city, Nigeria. A total of 11 urine and swab samples were studied between February 2021 to April 2021. This study was extrapolated from a wider study of MDRE and MRSA prevalence among patients in health centers in Benin-city, Nigeria. Microbial enumeration and identification were carried out using cultural and biochemical methods. Microbial counts were carried out using cultural characterization, Gram staining techniques and biochemical tests including; oxidase, indole, sugar fermentation, citrate, motility, methyl red, catalase, urease and antimicrobial susceptibility test (using Kirby-Bauer disc diffusion technique). Most of the samples tested were positive for S. aureus and MRSA. From the study, it was observed that, patients between the ages of 18-24 and 25-34 had the highest percentage of MRSA (45.5%), while females had a higher percentage (54.6%) than males, other works had the highest frequency of 36.4% and Patients receiving between 11,000-99,999 had the highest percentage of 77.8%. Findings from this study revealed that both S. aureus and MRSA had high prevalence in the distribution by participants’ social demographic characteristics. Therefore, MRSA poses a potential public health risk and ntimicrobial sensitivity and resistance must ultimately be understood at the population, organism, cellular, and molecular levels if
antimicrobial resistance is to be reduced.

Modern agriculture and industries are dependent on a variety of synthetic chemical compounds, including pesticides. Their extensive exploitation has resulted in the contamination of natural environment. This study investigates the effects of the combination these two chemicals, Haloxyfop-R-methyl ester + Dichlorvos, on nitrifying bacteria populations, specifically Nitrosomonas sp and Nitrobacter sp, within soil samples. Random collection of soil samples was collected from the University of Benin farmland sprayed with the appropriate dosage of the combined chemicals. The soil samples were obtained from four points. This research spanned a 28-day period, with sampling conducted at day 0, day 14, and day 28. Isolation of Nitrosomonas sp and Nitrobacter sp using Winogradsky medium 1 and 2 involved culturing diluted soil samples in Winogradsky 1 and 2 media. The study results showed a Nitrosomonas count of 3×103 ± 424.26 and Nitrobacter count of 8.6×103 ±
2262.74.

ABSTRACT
Pesticides are chemicals widely used in agriculture to control diseases and to help increase crop
yield. Pesticides in particular insecticides can be very beneficial but have also been found to have
harmful side effects on non-target insects. The effects of pesticides are not simply linear but
complex through their interactions with a large variety of biotic and abiotic factors. Pesticides is
a general word that describes numerous groups of insecticides, fungicides, herbicides, garden
chemicals, household disinfectant sand rodents that are operated to both destroy and protect from
pests. Rhizobacteria are root associated bacteria that can have detrimental, neutral or beneficial
effect on plant grow. Nitrogen fixation is one of the beneficial processes performed by
rhizobacteria. Plant growth promoting rhizobacteria were first identified by Kloepper and
Schroth et al., (1978) to be soil bacteria that colonize the roots of plants following inoculation
onto seed and that enhance plant growth. Pesticides that persist in soil may have a long-lasting
impact on Rhizobial survival and function. The soil was sprayed with the combination of the
chemicals (Haloxyfop R Methyl Ester and Dichlovos) after they were diluted. Soil samples were
obtained from the University of Benin (UNIBEN), life science land and were wrapped in a clean
sterile polythene bag and labelled control and mixture of both chemicals. The materials for the
experiment were sterilized, the differential agars were prepared and the soil samples were diluted.
Distinct colonies were identified after growth were observed on the nutrient agar, these were
restreaked on a freshly prepared agar to obtain the pure culture and incubated at 37°C for 24
hours. Growth on Bacillus cereus agar and Eosin methylene blue agar were observed by colony
forms, colours and spore morphology. Using the nitrogen free medium, pure cultures were
inoculated and incubated at 28°C for 1-7 days and growth on these plates confirms the ability to
fix nitrogen. The results showed a gradual increase in the microbial count across 28 days (from
3.8×104 ± 707.11 to 4.9×104 ± 4949.75). Also there was little or no effect on plant growth
promoting rhizobacterial activities of isolated microorganisms such as Pseudomonas aeruginosa,
Escherichia coli and Bacillus subtilis. Chemicals that have little or no effects on the plant
growth promoting rhizobacterial abilities of microorganisms should be used on farmlands.