The 9th International Conference on Agricultural and Biological Sciences (ABS 2023)

Abstract: The emergence of multidrug resistant bacteria is a global problem and major obstacle for the treatment of many infectious diseases. Indiscriminate, unnecessary, and unwise use of antibiotics boosts up this antibiotic resistance giving rise to multidrug-resistant (MDR) bacteria in the environment. The role of the hospital environment as a reservoir of multidrug-resistant Enterococcus spp. in Dhaka has been poorly investigated; however, it could be responsible for the transmission of multidrug-resistant bacteria.
Enterococci are indicators of the presence of fecal material in water and, therefore, of the possible presence of disease-causing bacteria, viruses, and protozoa. Enterococci are organisms with remarkable ability to adapt to the environment and acquire antibiotic resistance determinants. It is now a global concern as the innocent, easily treatable bacteria are slowly making changes resistant to antimicrobial agents because of careless, rapid, and widespread use. Freshwater environments are a well-recognized system for the dissemination and evolution of antibiotic resistance. Water bodies are sites of genetic exchange where environmental bacteria interact with microbes originated from humans and other animal sources, through horizontal gene transfer. Enterococci are indigenous flora of the gastro-intestinal tracts of animals and humans. Recently, interest in two major species, Enterococcus faecium and Enterococcus faecalis, has heightened because of their ability to cause serious infections and their intrinsic resistance to antimicrobials. So, the aim of the present study was performed to see the status of hospitals in Dhaka city and aquatic habitats as the global concern of rising antibiotic resistance Enterococcus spp. which has become a threat to humans.
Enterococci are ubiquitous. The origins of Enterococcus species vary from environmental to animal and human sources. Enterococcus faecalis and E. faecium are the predominant, gram positive cocci in human stools. Animals like poultry, cattle, and pig, E. faecium is the prevalent species, but other species occur like E. faecalis, E cecorum, E. gallinarum, and E. durans. Because of unusual use of antibiotics, these bacteria grow high level resistance among them against multiple drugs.
The present study aimed to enumerate, isolate, and characterize antibiotic resistant Enterococcus spp. from freshwater habitats. Fifty-one samples were collected from ten different hospitals and 90 samples were collected from nine different freshwater habitats in Dhaka city. The pH of the collected samples ranged 7.18 - 8.45. Enterococcus agar medium was used to enumerate, isolate, and characterize bacteria. In Enterococcus agar, the bacterial load ranged 1.10 × 101 - 3.71 × 102 cfu/g.
Out of initial 177 bacterial isolates, finally 21 isolates were selected for detail studies considering their growth pattern, morphological and physiological characteristics. All the selected isolates were facultative anaerobic, gram positive, cocci shaped and non-spore former. Enterococcus were phenotypically identified considering their colonial morphology and physiological and biochemical characteristics. Out of eleven isolates nine were E. faecium and two were E. faecalis.
The antimicrobial resistant pattern of the selected isolates to eight antibiotics were determined using disk diffusion method. E. faecium (60.52%) were more resistant to most of the antibiotics than E. faecalis (56.25%). All the isolates were shown to be resistant to antibiotics viz; Erythromycin, Tetracycline, Amoxycillin, Penicillin, Gentamycin, Chloramphenicol, Ciprofloxacin and Vancomycin. Enterococcus faecalis showed resistance to all 8 antibiotics tested as Erythromycin (78.57%), Tetracycline (21.43%), Amoxycillin (50%), Penicillin (57.14%), Gentamycin (28.57%), Chloramphenicol (92.86%), Ciprofloxacin (71.43%) and Vancomycin (42.86%). Furthermore, Enterococcus faecium exhibited resistance to Erythromycin (98.41%), Tetracycline (41.27%), Amoxycillin (36.51%), Penicillin (73.02%), Gentamycin (20.63%), Chloramphenicol (84.13%), Ciprofloxacin (82.54%) and Vancomycin (47.62%).
Remarkable multiple antibiotic resistances to the classes of antibiotic tested were observed between two species. An active sustainable program should be carefully developed to prevent the emergence of these multidrug resistant bacteria. If antimicrobial resistance continues to increase from current levels, it is estimated that by 2050 ten million people would die every year due to lack of available treatment and the world’s GDP would be reduced to 2-3.5%. More study needs to be formulated to find out the mechanism of multidrug resistant activities with possible preventive measures.

Biography: Dr. Md. Abdul Karim is a Professor and Principal Investigator of bioremediation of wastewater, microbiota in fish guts and seasonal dynamics of bioaerosols in the capital city in the Environmental Microbiology and Biotechnology Laboratory, Department of Botany, University of Dhaka, Dhaka 1000. He earned his PhD at Ehime University, Japan. Research in his lab focuses on understanding how to evaluate and control microbial activities in eutrophic environments. His current project includes 1) Bioremediation of eutrophic environments, 2) seasonal variation of bioaerosols, 3) Characterization of hydrocarbon and textile dye degrading bacteria, 4) Isolation and characterization of multidrug resistant bacteria from environmental samples and hospital wastes; 5) microbiota in fish guts and their antibiogram; and 6) Understanding of how pathogenic bacteria can survive longer period in adverse condition in association with other microorganisms and their interrelationship. He has supervised over 31 postgraduates and PhD. He has published 65 peer-reviewed papers in microbiology, author of 12 book chapters and 3 research books.

Prof. Karim is a member of editorial board of Bangladesh Journal of Botany (BJB); Science International; World Journal of Applied Sciences; International Journal of Biosciences; Journal of Biodiversity and Environmental Sciences; Microbiology Research International, Journal of Biological Sciences. He was awarded by the University Grants Commission in recognition of his outstanding performance in his field.