Determination of antimicrobial susceptibility and biofilm production in Staphylococcus aureus isolated from white coats of health university students

Contamination of Clinical White Coats with Potential Pathogens and their Antibiotic Resistant Phenotypes Among a Group of Sri Lankan Medical Students

Background: Clinical white coats worn by the medical students can be contaminated at hospitals and act as a potential reservoir for pathogens including antibiotic-resistant bacteria. This study aimed to identify the contamination rates of clinical white coats worn by medical students with selected potential pathogens and their antibiotic resistant phenotypes. Methods: A cross-sectional study was done among 151 4th year medical students of Faculty of Medicine, University of Peradeniya, Sri Lanka in September 2020. The participants belonged to two batches undergoing clinical training at two settings. Swabs from pockets and sleeves of the clinical white coats were taken. Potential pathogens and their resistant phenotypes were identified with routine tests. Results: Fifty-three participants (35.1%) had coats contaminated with Staphylococcus aureus; 15 (9.9%) had coats contaminated with Methicillin-Resistant S.aureus (MRSA).  One Enterobacterales (0.7%) was an AmpC producer.  Enterococcus species were isolated from 19 (12.6%) coats and 2 (1.3%) had coats contaminated with vancomycin resistant enterococci.  Molecular testing on the MRSA isolates identified that 5(20%) of the MRSA isolates were PVL positive while all were mecA positive. Sex, type of clinical appointment, and frequency of washing white coats were not associated with contamination. The “batch” was significantly associated with contamination with S.aureus and Enterococcus species.  Conclusions: We found that clinical white coats worn by medical students recruited for the study were contaminated with S.aureus, MRSA and Enterococcus species. There was a notably high-rate of contamination with S. aureus.  All MRSA isolates were mecA positive while the rate of PVL positivity was low.

Molecular Characterization of Gene-Mediated Resistance and Susceptibility of ESKAPE Clinical Isolates to Cistus monspeliensis L. and Cistus salviifolius L. Extracts

Background

Multidrug resistance (MDR) and extensively drug-resistant (XDR) are now the biggest threats to human beings. Alternative antimicrobial regimens to conventional antibiotic paradigms are extensively searched. Although Cistus extracts have long been used for infections in traditional folk medicines around the world, their efficacy against resistant bacteria still needs to be elucidated. We aim to investigate the antibiotic susceptibility profiles of clinical strains Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter cloacae (acronym “ESKAPE”), and their resistance mechanisms by PCR, as well as their sensitivity to C. monspeliensis (CM) and C. salviifolius (CS) methanol extracts and their fractions.

Methods

Antibiotic susceptibility profile and resistance mechanism were done by antibiogram and PCR. Fractions of CM and CS were obtained using maceration and Soxhlet; their antibacterial activities were evaluated by determining inhibition zone diameter (IZD), minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC).

Results

Results revealed that all strains were XDR except S. aureus, which was MDR. The PCR indicates the presence of gene-mediated resistance (bla_CTX-M, bla_SHV, bla_OXA-48, bla_NDM, bla_OXA-51, bla_OXA-58, bla_IMP, bla_VIM, and bla_mecA). Also, maceration was slightly better for bioactivity preservation. Overall, the extracts of CM (IZD = 20 mm, MIC = 0.01 mg/mL) were more active than those of CS. All extracts inhibited MRSA (methicillin-resistant Staphylococcus aureus) and ERV (Enterococcus faecium Vancomycin-Resistant) with interesting MICs. The ethyl acetate fraction manifested great efficacy against all strains. Monoterpene hydrocarbons and sesquiterpenes oxygenated were the chemical classes of compounds dominating the analyzed fractions. Viridiflorol was the major compound in ethyl acetate fractions of 59.84% and 70.77% for CM and CS, respectively.

Conclusions

The superior activity of extracts to conventional antibiotics was seen for the first time in the pathogens group, and their bactericidal effect could be a promising alternative for developing clinical antibacterial agents against MDR and XDR ESKAPE bacteria.

Presence of Methicillin-Resistant Staphylococcus aureus (MRSA) on Healthcare Workers' Attire: A Systematic Review

Contaminated healthcare workers' (HCW) clothing risk transferring methicillin-resistant Staphylococcus aureus (MRSA) in healthcare facilities. We performed a systematic review in Pubmed and Scopus for 2000-2020 according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to analyze evidence of MRSA on HCW attire. The primary study outcome was MRSA isolation rates on HCW clothing in healthcare settings. Out of 4425 articles, 23 studies were included: 18 with 1760 HCWs, four with 9755 HCW-patient interactions and one with 512 samples. There was a notable variation in HCWs surveyed, HCW attires, sampling techniques, culture methods and laundering practices. HCW attire was frequently colonized with MRSA with the highest rates in long-sleeved white coats (up to 79%) and ties (up to 32%). Eight studies reported additional multidrug-resistant bacteria on the sampled attire. HCW attire, particularly long-sleeved white coats and ties, is frequently contaminated with MRSA. Banning certain types and giving preference to in-house laundering in combination with contact precautions can effectively decrease MRSA contamination and spread.