Kindu Geta

Background: To overcome antibiotic resistance, there is an interest in improving or discovering novel classes of antibiotics from microorganisms that have different mechanisms of action worldwide. In Ethiopia, no significant studies have been conducted to isolate antibiotic-producing bacteria from hotspot environments and evaluate their antagonistic activities against multidrug-resistant bacteria. Therefore, the present study aimed to isolate antibacterial-producing bacteria from wastes and evaluate their antagonistic activities against multidrug-resistant bacteria in Bahir Dar town. Methods: A total of 49 bacteria were isolated from 30 waste and soil samples and tested against multidrug-resistant bacteria by primary screening using the single line streak method. Crude extracts of promising isolates were produced using submerged state fermentation methods and tested against multidrug-resistant bacteria using agar well diffusion methods. The minimum inhibitory and bactericidal concentrations of the crude extracts were determined using two-fold serial dilution and streak plate methods. Results: The results revealed that 11 (22.5%) bacterial isolates showed antibacterial activity against 1 or more tested multidrug-resistant bacteria. Isolates Ampb17 and Ampb33 isolated from soil and poultry waste showed the highest antagonistic activity against Salmonella spp., with a mean zone of inhibition of 20.3 ± 0.3 mm. The crude extract from isolate Ampb30, isolated from dairy waste, showed the highest antibacterial activity against Salmonella spp., with a mean zone of inhibition of 27.7 ± 0.3 mm. One-way analysis of variance confirmed that most of the crude extracts were statistically significant at a 95% confidence interval. The minimum inhibitory concentration of crude extracts was 0.13 mg/ml against S. aureus, E. coli, Salmonella spp., Pseudomonas spp., and Klebsiella spp., whereas the minimum bactericidal concentration of crude extracts was 0.25 mg/ml against S. aureus, E. coli, Salmonella spp., and Pseudomonas spp. Conclusion: The results of the present study revealed that antibiotic-producing bacteria from waste and soil have vast potential sources of antibacterial compounds.

Background: Wastes generated from hotspot environments contain a wide range of antibiotics and pathogens that play a significant role in the dissemination of antibiotic-resistant bacteria in the environment. This study was carried out to isolate bacteria from hotspot environments and determine their resistance profiles to commonly used antibiotics in Bahir Dar city, Ethiopia. Methods: A cross-sectional study was conducted from October 2020 to June 2021 in Bahir Dar City. A total of 126 waste and wastewater samples were aseptically collected, transported, and processed for bacteriological isolation and susceptibility testing following standard procedures. Results: A total of 411 bacterial isolates were recovered and the highest value of 122 (29.7%) bacterial isolates were obtained from medical wastewater samples, and the most frequently isolated bacteria were assigned to the species Escherichia coli with 82 strains (19.5%). The results revealed that the highest resistance profile of 69 (95.8%) was obtained in Staphylococcus aureus against ampicillin and 46 (86.8%) Citrobacter spp. against tetracycline. Two hundred and sixteen (52.6%) of bacteria showed multi-drug resistance and the highest multi-drug resistance was observed in Pseudomonas spp. 47 (65.3%), followed by Escherichia coli 51 (62.2%). The highest resistance profile of 12 (85.7%) and 60 (74.1%) for tetracycline were obtained from beef waste and wastewater and medical wastewater samples. The highest multi-drug resistance was recorded in isolates isolated from beef waste and wastewater samples 11 (64.7%), followed by medical wastewater samples 84 (64.1%). Even though a higher (> 0.2) multi-antibiotic resistance index was found in all hotspot environments, the highest multi-antibiotic resistance index (0.477) was recorded in bacteria isolated from medical wastewater. Conclusion: It was concluded that wastes generated from hotspot environments and released in the environment contain large numbers of antibiotic-resistant, multidrug, extensively, and pan-drug-resistant bacteria. Proper waste management strategies should be established. Graphical Abstract:

Background: Although inappropriate antibiotic use could contribute to the spread of antimicrobial resistance, data on the knowledge, attitude and practice of antibiotic use and resistance among patients in north-western Ethiopia are scarce. This study assessed patients’ knowledge, attitudes and practices regarding antibiotic use and resistance in selected public hospitals of Amhara regional state, Ethiopia. Methods: A cross-sectional study was conducted in selected public hospitals of Amhara regional state from November to December 2020 to assess the knowledge, attitude, and practice of patients on antibiotic resistance and use. Data were collected from 233 participants using a structured questionnaire and analyzed using SPSS version 23. Results: According to the findings, 60.3% of the participants obtained their antibiotics without a prescription from private pharmacies, and the most commonly used antibiotic to treat human diseases was ampicillin (70.7%). Even though 69.8% of the patients heard about antibiotics and antibiotic resistance from several sources, 68.1– 87.9% of them were unaware on the factors that contribute to the transmission of resistant bacteria to humans and the impact of antibiotic resistance on human and animal health. Using the mean score of 3.15 ± 0.08 as the cut-off, 37.5% of patients know about antimicrobial resistance and use. With a mean score of 27.6 ± 0.3, 45.3% of patients had positive attitudes toward prudent antibiotic use and resistance. About 44% of participants had a good practice, with a mean practice score of 4.95 ± 0.17. A higher level of education was associated with better knowledge, positive attitudes, and better practices regarding antibiotic use and resistance. Although 57.3% of respondents viewed poor handwashing practices in hospitals as a major factor contributing to increased antibiotic resistance, 59.9% of respondents viewed implementing hygiene, infection prevention, and control practices as a major strategy contributing to reducing antibiotic use and resistance. Conclusion: According to the present study, there is a low level of awareness among patients about the proper antibiotics use and resistance. It is essential to raise awareness, develop, and implement interventions to reduce antimicrobial use and antibiotic resistance in the study area.

Inappropriate use of antibiotics in animal and human plays a role in the emergence and spread of bacteria resistant to antibiotics which threatens human health significantly. Although extensive use of these antibiotics could contribute to the development of drug resistance, information on the knowledge, attitude and practice of antimicrobial resistance and use among animal farm owners/workers in north western Ethiopia is rare. The objective of the present study was to assess knowledge, attitude and practice of animal farm owner/workers towards antibiotic resistance and use in Amhara regional state north western Ethiopia. A cross sectional study was conducted in selected cities of Amhara regional state from January to February, 2020. Data was collected from 91 participants using structured questionnaire and analyzed using SPSSS version 23. The results showed that 96.7% of respondents gave antibiotics to treat their livestock from different sources. Most of the respondents bought their antibiotics from private pharmacies without prescription and the most frequently mentioned antibiotics used to treat animal diseases was tetracycline (76.9%), followed by ampicillin (72.5%). Although, 90.1% of the animal farm owners heard about antibiotics and antibiotic resistance from different sources, they did not know the factors contributing to the transmission of resistant bacteria to humans and the impact of antibiotic resistance on human and animals’ health. Using the mean score 4.44 ± 0.15 as the cut-off, half of the animal farm owners/workers had good knowledge about antimicrobial resistance and use. 52.5% of animal farm owners/workers had positive attitudes towards wise antibiotic use and resistance with a mean score of 28.4 ± 0.5. However, 52.75% participants had poor practice with the mean score of practice 4.95 ± 0.17. Better knowledge, positive attitudes and better practices on antibiotic use and resistance were associated with farm owners/workers who engaged in higher education. Although poor awareness on antimicrobial resistance was perceived by 76.9% of respondents as very important factors that contribute to increasing antibiotic resistance, increasing the use of complementary treatments was perceived by the majority of respondents as very important strategies that contribute to reduce antibiotic use and resistance. The current study disclosed that there is low level of awareness among animal farm owners about the correct use of antibiotics and resistance. It is necessary to raise awareness, develop and implement interventions to reduce antimicrobial use and antibiotic resistance in the study area.

Background: Infectious diseases caused by bacteria have a large impact on public health. Increasingly resistant microbial infections intensified the search for new, safer, and more efficacious agents to combat serious microbial infections. Plants have played a central part in combating many diseases in human and domestic animals in many local communities, including Africa. Rhamnus prinoides is Ethiopian medicinal plants that have been used traditionally for the treatment of diverse infectious diseases. Therefore, this research was carried out to evaluate the antibacterial activity of Rhamnus prinoides extracts against pathogenic bacteria. Methods: The antimicrobial activity tests were carried out by the agar well diffusion method. Broth dilution and streak plate methods were used to determine MIC and MBC values of extracts respectively. Results: The results revealed that ethanol extracts of fruits showed the highest antibacterial activity against standard strains of S. aureus with mean inhibition zone of 26± 0.58, 28.33±1.2 and 33.33± 0.9 mm at 25, 50 and 100 mg/ml respectively. The lowest mean MIC value (1.04 mg/ml) was recorded with ethanol extract of fruits against the standard strains of S. aureus and the lowest mean MBC value (2.08 mg/ml) was recorded with ethanol extract of fruits against the standard strains and clinical isolates of S. aureus. Conclusion: On the basis of the current findings, Rhamnus prinoides could be a good candidate in the search for new antibacterial agents from natural products against bacterial pathogens. Therefore, further studies are needed to study their toxicology and isolate the bio- active components from this plant.

Medicinal plants offer a major and accessible source of health care to people living in developing countries. Increasing in resistant microbial infections intensified the search for new, safer, and more efficacious agents to combat serious microbial infections. Acanthus sennii is one of the medicinal plants used traditionally for treatment of different infectious diseases in Ethiopian. Therefore, this research was carried out to evaluate antibacterial activity of Acanthus sennii against pathogenic bacteria. The antimicrobial activity tests of the plant extracts against pathogenic bacteria were carried out by the agar well diffusion method. Broth dilution and streak plate method were used to determine MIC and MBC of extracts respectively. The results revealed that ethanol extracts of leaves showed the highest antibacterial activity against standard strains of S.aureus with inhibition zone of 14±0.58mm and 17±0.67mm at 50mg/ml and at 25mg/ml respectively. Ethanol extracts of buds showed the highest antibacterial activity against standard strains of S.aureus with inhibition zone of 25.67±0.67mm at 100mg/ml. The lowest mean MIC value (2.6±0.52 mg/ml) was recorded with ethanol extract of leaves against standard strains and clinical isolates of S. aureus. The lowest mean MBC value (4.2±1.04 mg/ml) was recorded with ethanol extract of leaves against standard strains of S. aureu. Acanthus sennii could be a good candidate in the search for new antibacterial agents from natural products against bacterial pathogens. Therefore, further studies are needed to study their toxicology and isolate the bio- active components from this plant. Key words: Acanthus sennii, Antibacterial activity, MIC, MBC, pathogenic bacteria

Background: Infectious diseases caused by bacteria have a large impact on public health. Increasing in resistant microbial infections intensified the search for new, safer, and more efficacious agents to combat serious microbial infections. Plants have played a central part in combating many diseases in human and domestic animal in many local communities, including Africa. Rhamnus prinoides is Ethiopian medicinal plants that have been used traditionally for the treatment of diverse infectious diseases. Therefore, this research was carried out to evaluate antibacterial activity Rhamnus prinoides extracts against pathogenic bacteria. Methods: The antimicrobial activity tests were carried out by the agar well diffusion method. Broth dilution and streak plate methods were used to determine MIC and MBC of extracts respectively. Results: The results revealed that ethanol extracts of fruits showed the highest antibacterial activity against standard strains of S.aureus with mean inhibition zone of 26±0.58, 28.33±1.2 and 33.33±0.9mm at 25, 50 and 100mg/ml respectively. The lowest mean MIC value (1.04 mg/ml) was recorded with ethanol extract of fruits against standard strains of S. aureus and the lowest mean MBC value (2.08 mg/ml) was recorded with ethanol extract of fruits against standard strains and clinical isolates of S. aureu. Conclusion: On the basis of the current findings, Rhamnus prinoides could be a good candidate in the search for new antibacterial agents from natural products against bacterial pathogens. Therefore, further studies are needed to study their toxicology and isolate the bio- active components from this plant. Key words: Antibacterial activity, Escherichia coli, MBC, MIC, Rhamnus prinoides, Staphylococcus aureus