A molecular epidemiological study of methicillin-resistant and methicillin-susceptible <em>Staphylococcus aureus</em> contamination in the airport environment

Abstract

BackgroundMethicillin-resistant Staphylococcus aureus (MRSA) causes a wide variety of serious infections worldwide. There are few studies on the prevalence, antimicrobial susceptibility, and molecular characteristics of MRSA contamination in the environment of airports.Materials and methodsA cross-sectional survey was conducted in Guangzhou Baiyun Airport. Environmental surface sampling was conducted in frequently touched locations for S. aureus analysis. All isolates were characterized by multilocus sequence typing (MLST) and tested for antimicrobial susceptibility, resistance genes, and virulence genes. Data were analyzed by chi-squared test and correspondence analysis.ResultsOf the 1,054 surface samples, the contamination rate was 7.2% (76/1,054) for S. aureus and 2.2% (23/1,054) for MRSA. There were 62.9% (56/89) S. aureus isolates classified as multidrug resistant (MDR), with six linezolid-resistant isolates and two cfr-carrying isolates. The most prevalent S. aureus genotypes were CC6 (ST6), CC59 (ST59), and CC188 (ST188), with ST59-MRSA-IV (pvl–) as the predominant MRSA. There were significant differences between methicillin-resistant and methicillin-sensitive isolates in rates of resistance to tetracycline (P<0.001) and sek carriage (P=0.029). The correspondence analyses revealed significant corresponding relationships between genotypes and phenotype–genotype characteristics of S. aureus isolates.ConclusionOur findings revealed a potential risk of cross-transmission of MRSA between human beings and environments, suggesting more stringent contamination control measures. In addition, this study revealed significant corresponding relationships between genotypes and phenotype–genotype characteristics of S. aureus isolates, which may provide new ideas for monitoring the latest epidemiological trends.

Molecular characterization of methicillin-resistant Staphylococcus aureus clinical strains from the endotracheal tubes of patients with nosocomial pneumonia

“…Despite the marked heterogeneity of the sequence types in this study, CC22 and CC5 were the main clonal complexes detected. Specific resistance mechanisms can be associated with clonality, since a higher number of these mechanisms were found in the widely expanded CC5 and CC22 clones than in the CC45 and CC59 clones [32]. Consistent with our results, previous studies (in the US, Portugal and Japan) have found CC5 and CC59 to be associated with extensive multi-drug resistance, but not CC45 [32].…”

“…Specific resistance mechanisms can be associated with clonality, since a higher number of these mechanisms were found in the widely expanded CC5 and CC22 clones than in the CC45 and CC59 clones [32]. Consistent with our results, previous studies (in the US, Portugal and Japan) have found CC5 and CC59 to be associated with extensive multi-drug resistance, but not CC45 [32]. Another important point to stress is that these CCs had previously been associated with virulent S. aureus strains.…”

“…Second, although we did not assess the virulence of our MRSA strains, some of the clonal complexes identified, such as the CC59 and CC45, have been shown to be closely related to virulent strains. Immune evasion cluster (IEC) genes have been associated with CC59 (IEC-hemolysin genes) and CC45 (IEC-enterotoxin-hemolysin genes) [32].…”

Community-Acquired Methicillin-Resistant Staphylococcus aureus Severe Infection in Two Healthy Patients with Ear Piercing

“…Staphylococcus aureus is a human opportunistic pathogen, and methicillin-resistant S. aureus (MRSA) causes a wide variety of infections worldwide, including hospital-associated MRSA (HA-MRSA) and community-associated MRSA (CA-MRSA) infections [5,6]. The last ones have the ability to infect people living in a community without personal or associated risk factors, suggesting enhanced bacterial virulence [5][6][7].…”

“…Staphylococcus aureus is a human opportunistic pathogen, and methicillin-resistant S. aureus (MRSA) causes a wide variety of infections worldwide, including hospital-associated MRSA (HA-MRSA) and community-associated MRSA (CA-MRSA) infections [5,6]. The last ones have the ability to infect people living in a community without personal or associated risk factors, suggesting enhanced bacterial virulence [5][6][7]. It´s a gram positive coccus that can spread from the skin to the lungs, the bloodstream or other body organs, being able to cause primary skin and soft tissue infections, mainly furunculosis and abscesses, but can also cause necrotizing tissue infections and fulminant pneumonia [8][9][10][11][12][13].…”