A diversity of Antibiotic-resistant Staphylococcus spp. in a Public Transportation System

Abstract

ObjectivesOur goal was to determine the diversity and abundance of Staphylococcus bacteria on different components of a public transportation system in a mid-sized US city (Portland, Oregon) and to examine the level of drug resistance in these bacteria.MethodsWe collected 70 samples from 2 cm × 4 cm sections from seven different areas on buses and trains in Portland, USA, taking 10 samples from each area. We isolated a subset of 14 suspected Staphylococcus spp. colonies based on phenotype, and constructed a phylogeny from16S rRNA sequences to assist in identification. We used the Kirbye–Bauer disk diffusion method to determine resistance levels to six common antibiotics.ResultsWe found a range of pathogenic Staphylococcus species. The mean bacterial colony counts were 97.1 on bus and train floors, 80.1 in cloth seats, 9.5 on handrails, 8.6 on seats and armrests at bus stops, 3.8 on the underside of seats, 2.2 on windows, and 1.8 on vinyl seats per 8 cm2 sample area. These differences were significant (p < 0.001). Of the 14 isolates sequenced, 11 were staphylococci, and of these, five were resistant to penicillin and ampicillin, while only two displayed intermediate resistance to bacitracin. All 11 isolates were sensitive to trimethoprim-sulfamethoxazole, vancomycin, and tetracycline.ConclusionsWe found six different strains of Staphylococcus, and while there were varying levels of drug resistance, we did not find extensive levels of multidrug-resistant bacteria, and no S. aureus was found. We found floors and cloth seats to be areas on buses and trains that showed particularly high levels of bacteria.

Characteristics of Antibiotic Resistance of Airborne Staphylococcus Isolated from Metro Stations

“…By 2011, over 120 cities worldwide will have metro systems [5], but only a few cities have investigated the bacterial populations in the metro, including London [6], Cairo [7], Seoul [8], Tokyo [9], Beijing [10] and Oslo [5]. Antibiotic-resistant Staphylococcus was reported in the public transportation system in Portland (OR, USA) [11]. This suggested the possibility that antibiotic resistant strains can be spread through passenger flow in buses and trains.…”

A molecular epidemiological study of methicillin-resistantStaphylococcienvironmental contamination in railway stations and coach stations in Guangzhou of China

“…; Yeh et al . ; Lutz et al . ) and performing preliminary experiments, we collected surface samples from several different locations: seats, Ticket Vending Machines (TVMs), elevators buttons, toilet faucets, booking desks and canteen desks.…”

“…Some studies have found that environmental surfaces of transportation showed particularly higher prevalence of methicillin‐resistant Staphylococci (Yeh et al . ; Peng et al . ).…”

“…However, there are few studies focused on the epidemiology of MRSA in public place environments, such as transportation, beaches, schools and so on (Goodwin et al 2012;Mbogori et al 2013). Some studies have found that environmental surfaces of transportation showed particularly higher prevalence of methicillin-resistant Staphylococci (Yeh et al 2011;Peng et al 2015). Moreover, several studies have confirmed that environment is an important medium and vectors for dissemination of S. aureus in population (Hardy et al 2006).…”

Is the Public Transportation System Safe from a Public Health Perspective?

“…The authors found six different strains of Staphylococcus, and while there were varying levels of drug resistance, they did not find extensive levels of multi-drug-resistant bacteria,and no S. aureus was found. Floors and cloth seats on buses and trains had particularly high levels of bacteria.These findings can inform both personal hygiene and public policy regarding cleaning frequency or areas on which to focus cleaning efforts, as well as choice of seat type (cloth vs. vinyl) to minimize exposure to potentially harmful bacteria [10].…”