Nasal carriage rate and associated risk factors of Staphylococcus lugdunensis isolated from healthy people in the Duhok-Kurdistan region of Iraq

Abstract

Aims:The aim of the study was to investigate the prevalence, antibiogram and associated risk factors of Staphylococcus lugdunensis among healthy people. Methodology and results: A total of 200 nasal samples were collected from participants. The swabs were cultured on mannitol salt agar and incubated at 37 °C for 24 h. Isolates were diagnosed based on phenotypic, biochemical reactions and molecular methods. All identified isolates were screened for susceptibility to ten different antibiotics. Based on Gram stain and biochemical tests, 65 out of 200 (32.5%) were identified as S. lugdunensis. Twenty-nine of 65 (34.5%) were from males and 36 of 65 (31%) were from females (p=0.603). The highest prevalence was observed in the age group of 31-40 years (40%; 16/41) and the least prevalence rate was among the age group of ≥51 (15.4%; 2/13) (p=0.533). No statistically significant difference in the prevalence of S. lugdunensis was observed among people according to their family member size (p=0.472). Additionally, a slight difference in the carriage rate of S. lugdunensis was observed among the people who had Coronavirus disease (Covid-19) infection (31%) and the people who had no previous infection with it (33.6%) (p=0.697). Also, no statistically significant difference (p=0.992) in the nasal carriage rate of S. lugdunensis was observed among smokers (32.5%; 12/37) and nonsmokers (32.5%; 53/163). All isolates were 100% susceptible to doxycycline, linezolid and chloramphenicol; 99% to oxacillin; 92% to ciprofloxacin; 91% to amikacin; 89% to nitrofurans and vancomycin; 83% to meropenem; and 75% to erythromycin. Also, 15.4% of the isolates were multidrug resistant. Conclusion, significance and impact of study: Results revealed that the prevalence of nasal S. lugdunensis was high among people with no specific associated risk factor. Also, a high rate of antibiotic resistance was observed with a high rate of multidrug resistance. Hence, education programs and improving hygienic measures are necessary to prevent the spread of multidrug resistance to S. lugdunensis. This can help as an effective measure to control bacterial infections.