ABSTRACT
Background: Enterococci have emerged as a major cause of nosocomial infections and within this group, Enterococcus faecalis and Enterococcus faecium cause the majority of human and livestock enterococcal infections. In this article, we tried to determine antibiotics and metals resistance patterns of E. faecalis and E. faecium strains
Methods: One hundred sixty different strains of E. faecalis and E. faecium were collected from livestock sewage and the human fecal waste during 15 months. Then bacterial antibiotics sensitivity tests were carried out using the Agar disc diffusion method
Results: Generally, 100% of E. faecalis strains separated from human and livestock sources [i.e. sheep] showed penicillin [P]/ kanamycin [K]/ nitrofurantoin [N]/ loracarbef [L]/ Ciprofloxacin [Cc]/ ampicillin [AN]/ nalidixic acid [NA]/ sulfamethoxazole [S] antibiotics resistance patterns. In addition, 55% of isolated E. faecium showed P/S/AN/NA antibiotics resistance patterns. Each strain showed a resistance to at least two aminoglycoside antibiotics. However, E. faecalis strains from human and the livestock sources showed 94% and 100% of resistance to nitrofurantoin, respectively. The effects of different metal concentrations was evaluated in both strains. The agar dilution method was applied in this stage. Hg at 0.05 mmol/L of minimum inhibitory concentration [MIC] showed toxicity to both the human and livestock Enterococcus strains. Cadmium at 1 mmol/L and 0.5 mmol/L concentrations had the most toxicity to E. faecalis and E. faecium strains, respectively. Obviously, toxicity to bacteria is less than other metals. As a result, Zn/Ni/Cu/Co resistance pattern is suggested for both strains. Finally, antibiotics and heavy metals resistance patterns were monitored simultaneously
Conclusion: Almost all E. faecalis strains isolated from humans and livestock showed antibiotics and heavy metals resistance patterns of P/K/L/Cc/S/AN/NA/Zn/Cu/Co simultaneously. Moreover, 55% of E. faecium strains showed similar antibiotics and heavy metals resistance patterns of P/S/AN/NA/Zn/Ni/Cu/Co
ABSTRACT
Vibrio species have been known as the cause of gastrointestinal and extraintestinal disorders, which usually appear epidemically in some seasons of the year. Since the sea has been known as one of the important ecosystems of Vibrio species, this study was carried out with the aim of determining the prevalence of Vibrio species and their microbial resistance in different coastal regions of the south of country in different seasons of year. In this descriptive cross-sectional study, 600 water samples taken from the coastal waters of Bandar Abbas were evaluated in terms of presence of Vibrio strains in two seasons of spring and winter. For primary detection, alkaline peptone water and TCBS were used, and the final identification was carried out using biochemical tests [oxidase, motility, Indole ring, KIA, and other biochemical tests such as 0% NaCl, 6% NaCl, VP, and ONPG]. V. harveyi [2.3%], V. cholerae [1.7%], V. parahaemolyticus [1.3%], V. furnissii [1.2%], V. metschnikovii [1%], P. shigelloides [1%], A. hydrophila [0.5%], V. vulnificus and V. mimicus [0.3%], and V. fluvialis [0.2%] had the highest prevalence. Also, in terms of the studied seasons, 71.2% of the contamination was related to winter season and 28.8% to spring season, which showed that the cases of contamination in winter was higher than in spring. Based on the study of researchers, the isolation of these species increases after rain. In the present study, this parameter had a positive effect on the isolation of Vibrio species.