Isolation and characterization of antimicrobial-resistant Escherichia coli from national horse racetracks and private horse-riding courses in Korea

Limited information is available regarding horse-associated antimicrobial resistant (AR) Escherichia (E.) coli. This study was designed to evaluate the frequency and characterize the pattern of AR E. coli from healthy horse-associated samples. A total of 143 E. coli (4.6%) were isolated from 3,078 samples collected from three national racetracks and 14 private horse-riding courses in Korea. Thirty of the E. coli isolates (21%) showed antimicrobial resistance to at least one antimicrobial agent, and four of the AR E. coli (13.3%) were defined as multi-drug resistance. Most of the AR E. coli harbored AR genes corresponding to their antimicrobial resistance phenotypes. Four of the AR E. coli carried class 1 integrase gene (intI1), a gene associated with multi-drug resistance. Pulsed-field gel electrophoretic analysis showed no genetic relatedness among AR E. coli isolated from different facilities; however, cross-transmissions between horses or horses and environments were detected in two facilities. Although cross-transmission of AR E. coli in horses and their environments was generally low, our study suggests a risk of transmission of AR bacteria between horses and humans. Further studies are needed to evaluate the risk of possible transmission of horse-associated AR bacteria to human communities through horse riders and horse-care workers.

Prevalence, antibiogram profile and cross transmission of Pseudomonas aeruginosa in a tertiary burn unit

Aims: Pseudomonas aeruginosa is an opportunistic pathogen that still develops life threatening infections in patients with immunological system defects like burns. The major problem with this organism is the ability to persist during infections due to its high rate of resistance to many drugs. This study was designed to evaluate the prevalence and drug susceptibility profile of Pseudomonas aeruginosa in patients admitted to a burn unit in a tertiary health facility. Methodology and Result: From 80 selected patients, appropriate clinical specimens from burn sites were collected and processed for the isolation and identification of Pseudomonas aeruginosa.. Also, 78 surveillance samples from various environmental sites and hands impressions of nursing staff in the burn unit were cultured for the isolation of Pseudomonas aeruginosa. Drug susceptibility profile showed high resistance for ceftazidime (40.7%) ciprofloxacin (13.1%) and piperacillin (34.6%); furthermore, low resistance for some antibiotics like imipenem (17.5%) pipereracillin/tazobactam (12.3%) and aztreonam (16%) were obtained. In addition, 8 multiresistant Pseudomonas aeruginosa (MRPA) isolates were recovered from clinical specimens and from environmental samples. Conclusion, significance and impact of study: Evidence of high prevalence of clinical and environmental MRPA reported in this study provides the rationale for strict enforcement of infection prevention protocol to minimize cross transmission of bacterial pathogens in hospital burn units and consequent disease burden arising from MRPA.

Nosocomial cross-transmission of Pseudomonas aeruginosa between patients in a tertiary intensive care unit.

Background: Nosocomial infection caused by Pseudomonas aeruginosa (P. aeruginosa) is very common, despite the application of various preventive measures in intensive care units (ICUs) leading to increased morbidity, mortality, prolonged hospital stay, and increased treatment cost. Aim: The aim of the present study is to identify the source of P. aeruginosa infection in patients admitted to tertiary ICU. Materials and Methods: From 200 patients selected randomly, appropriate clinical specimens from different sites were collected and processed for the isolation and identification of the nosocomial pathogens. Surveillance samples from environmental sites and hands of nursing staff were also cultured. Results: P. aeruginosa was found to be the most common pathogen associated with nosocomial infections accounting for 23.3% of all bacterial isolates from different infection sites in the ICU. Serotyping of the clinical isolates and surveillance sample isolates from nurses' hands showed serotype E as the most common serotype. Other serotypes of P. aeruginosa were isolated from environmental cultures such as sinks, floors, walls, tap water, etc. Conclusion: Study revealed a high prevalence of P. aeruginosa infections in the ICU attributed to cross transmission from patient to patient via hands of the nursing staff. Strict enforcement of infection control protocols is essential to minimize the disease burden.