Methicillin-Resistant Staphylococcus aureus Contamination of Frequently Touched Objects in Intensive Care Units: Potential Threat of Nosocomial Infections.

Background: Bacterial contamination in intensive care units is an important risk factor associated with increasing incidences of nosocomial infections. This study was conducted to study the bacterial colonization on commonly touched objects of intensive care units and antibiotic resistance pattern of bacterial isolates. Methods: This study was conducted in different intensive care units of Manipal Teaching Hospital, Pokhara, Nepal. A total of 235 swabs were collected from surfaces of bed rails, monitors, door handles, IV stands, telephone sets, nursing stations, medicine trolleys, sphygmomanometers, wash basin taps, dressing drums, stethoscopes, pulse oximeters, ventilators, defibrillators, and stretchers. Isolation, identification, and antibiotic susceptibility tests of the bacteria were performed following standard microbiological techniques. Results: Of 235 samples, bacterial growth was observed in 152 samples. A total of 90 samples of Staphylococcus aureus were isolated from 235 samples. Most of the sampling sites included in this study were found contaminated with S. aureus. The highest number of S. aureus was cultured from the surface of bed rails. Of the total S. aureus isolates, 54.4% (49/90) were methicillin-resistant Staphylococcus aureus (MRSA). Vancomycin resistance was detected among 8.1% MRSA isolates (4/49). Acinetobacter species were the commonest Gram-negative bacterial isolate. Conclusion: Bacterial contamination of the objects/instruments of the ICU was recorded to be high. The most common contaminating bacteria were S. aureus with a high percentage of MRSA and emergence of VRSA. Periodic microbiological surveillance, detection of contaminated sites, and effective decontamination methods would minimize the colonization by potential pathogens and their transmission.

Bacterial contamination of neonatal intensive care units: How safe are the neonates?

BACKGROUND: Intensive care units (ICU) are essential healthcare facility for life threatening conditions. Bacterial contamination of objects/instruments in ICU is an important source of nosocomial infections. This study is aimed to determine the level of bacterial contamination of instruments/objects which are commonly touched by healthcare workers and frequently come in contact with the neonates. METHODS: This hospital based prospective study was conducted in neonatal intensive care unit (NICU) of Manipal Teaching Hospital, Pokhara, Nepal. A total of 146 samples collected from surfaces of incubators, radiant warmers, suction tips, ventilators, stethoscopes, door handles, weighing machines, mothers' beds, phototherapy beds, laryngoscope, telephone sets, blood pressure machine, etc. formed the material of the study. Isolation, identification and antibiotic susceptibility of the bacterial isolates was performed by standard techniques. Blood culture isolates from NICU patients during the study period were compared with the environmental isolates. RESULTS: Out of 146 samples, bacterial growth was observed in 109. A total of 119 bacterial isolates were retrieved from 109 samples. Three common potential pathogens isolated were Escherichia coli (n = 27), Klebsiella species (n = 21) and Staphylococcus aureus (n = 18). Majority of E. coli and Klebsiella isolates were from incubators, suction tips and mothers' beds. Majority of S. aureus isolates were cultured from radiant warmers. Among S. aureus isolates, 33.3% (6/18) were methicillin resistant. Majority of the bacterial isolates were susceptible to gentamicin and amikacin. Common potential pathogens isolated from blood culture of NICU patients were S. aureus and Klebsiella species. CONCLUSION: High degree of bacterial contamination of objects/instruments in NICU was recorded. Isolation of potential pathogens like E. coli, Klebsiella species and S. aureus is a major threat of nosocomial infections. Blood culture data of NICU reflects possibility of nosocomial infections from contaminated sites. Gentamicin and amikacin may be used for empirical therapy in suspected cases of nosocomial infections in NICU.

Carbapenemase among Clinical Bacterial Isolates in Nepal.

Gram-negative isolates producing carbapenemase enzymes is a great public health problem in developing countries and their control is challenging task due to the involvement of multiple factors including the practice of self-medication, use of antibiotics on animal farms, poor hospital hygiene, etc. During this study, we searched various databases for relevant publication on carbapenemase-producing isolates in Nepal. Various classes of carbapenemases had been reported in Nepal. Most frequent was the New Delhi Metallo beta lactamase with many variants where NDM-1 was most prevalent. Similarly, Oxacillinase and Klebsiella pneumoniae carbapenemase producers were also prevalent in Nepal. While other carbapenemases like VIM, IPM, and DIM also detected. The isolates producing carbapenemases were extremely drug-resistant as they also co-produced various other carbapenemases, beta-lactamases, 16S rRNA methylase. Most isolates were resistant to many members of carbapenem, cephalosporin, quinolone, penicillin, aminoglycoside group of antibiotics. Such isolates had very few treatment options as only last line drugs like colistin, fosfomycin, and tigecycline was effective against most of these isolates. Carbapenemase production by almost all major human pathogens including E. coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter. Citrobacter, Proteus, Providencia is a matter of concern because some of these enzymes are located on plasmids and pose rapid dissemination among various gram-negative pathogens. Timely surveillance for carbapenemase producers throughout the nation, their proper treatment, and proper hospital hygiene to prevent nosocomial infections by carbapenemase producers, controlled use of carbapenems, educating health care workers, students and the general public about the adverse effects of antimicrobial resistance is imminent.

Detection and characterization of ESBL-producing Enterobacteriaceae from the gut of healthy chickens, Gallus gallus domesticus in rural Nepal: Dominance of CTX-M-15-non-ST131 Escherichia coli clones.

The surge in the prevalence of drug-resistant bacteria in poultry is a global concern as it may pose an extended threat to humans and animal health. The present study aimed to investigate the colonization proportion of extended-spectrum ß-lactamase (ESBL) and carbapenemase-producing Enterobacteriaceae (EPE and CPE, respectively) in the gut of healthy poultry, Gallus gallus domesticus in Kaski district of Western Nepal. Total, 113 pooled rectal swab specimens from 66 private household farms and 47 commercial poultry farms were collected by systematic random sampling from the Kaski district in western Nepal. Out of 113 pooled samples, 19 (28.8%) samples from 66 backyard farms, and 15 (31.9%) from 47 commercial broiler farms were positive for EPE. Of the 38 EPE strains isolated from 34 ESBL positive rectal swabs, 31(81.6%) were identified as Escherichia coli, five as Klebsiella pneumoniae (13.2%), and one each isolate of Enterobacter species and Citrobacter species (2.6%). Based on genotyping, 35/38 examined EPE strains (92.1%) were phylogroup-1 positive, and all these 35 strains (100%) had the CTX-M-15 gene and strains from phylogroup-2, and 9 were of CTX-M-2 and CTX-M-14, respectively. Among 38 ESBL positive isolates, 9 (23.7%) were Ambler class C (Amp C) co-producers, predominant were of DHA, followed by CIT genes. Two (6.5%) E. coli strains of ST131 belonged to clade C, rest 29/31 (93.5%) were non-ST131 E. coli. None of the isolates produced carbapenemase. Twenty isolates (52.6%) were in-vitro biofilm producers. Univariate analysis showed that the odd of ESBL carriage among commercial broilers were 1.160 times (95% CI 0.515, 2.613) higher than organically fed backyard flocks. This is the first study in Nepal, demonstrating the EPE colonization proportion, genotypes, and prevalence of high-risk clone E. coli ST131 among gut flora of healthy poultry. Our data indicated that CTX-M-15 was the most prevalent ESBL enzyme, mainly associated with E. coli belonging to non-ST131clones and the absence of carbapenemases.

Bacterial contamination of frequently touched objects in a tertiary care hospital of Pokhara, Nepal: how safe are our hands?

Background: Objects frequently touched by patients and healthcare workers in hospitals harbor potential pathogens and may act as source of infectious agents. This study aimed to determine the bacterial contamination of common hospital objects frequently touched by patients, visitors and healthcare workers. Methods: A total of 232 samples were collected from various sites like surface of biometric attendance devices, elevator buttons, door handles, staircase railings, telephone sets and water taps. Isolation, identification and antibiotic susceptibility testing of the isolates was performed by standard microbiological techniques. Biofilm forming ability of the S. aureus isolates was tested by a microtitre plate method. Results: A total of 232 samples were collected and 219 bacterial isolates were recovered from 181 samples. Staphylococcus aureus was the most common bacterial isolate (44/219). Majority of S. aureus isolates were recovered from elevator buttons, biometric attendance devices and door handles. Among the S. aureus isolates, 36.3% (16/44) were methicillin resistant Staphylococcus aureus (MRSA) while remaining were methicillin sensitive Staphylococcus aureus (MSSA). Out of 44 S. aureus isolates, 12 (29.5%) were multidrug resistant and 14 (31.8%) were biofilm producers. The majority of MRSA isolates 62.5% (10/16) were biofilm producers. Acinetobacter was the most common Gram negative isolate followed by E coli and Pseudomonas species. Conclusions: High bacterial contamination of frequently touched objects with variety of potential pathogens and normal flora was detected. S. aureus was the most common bacterial isolate. Biofilm forming ability offers additional survival advantage to the organisms on these objects. Present study highlights the need of improved hand hygiene among healthcare workers and regular cleaning/disinfection of sites of frequent public contact.

Nasal and Pharyngeal Colonization by Bacterial Pathogens: A Comparative Study between Preclinical and Clinical Sciences Medical Students.

BACKGROUND: Upper respiratory tract is one of the commonest sites for microbial colonization. The colonized individuals are at risk of infections and can be a source of transmission of pathogens. Medical students are frequently exposed to a variety of infectious agents and more likely to get colonized by them. This study was aimed to determine the prevalence and to compare the colonization rates of nasal and pharyngeal bacterial pathogens among preclinical and clinical sciences medical students. METHODS: This cross-sectional study was conducted among 100 preclinical and 100 clinical sciences medical students. Isolation, identification, and antibiotic susceptibility testing of the isolates were performed by standard microbiological techniques. RESULTS: The nasal colonization by S. aureus and MRSA was 35% (70/200) and 19.5% (39/200), respectively. The nasal colonization by S. aureus and MRSA was significantly higher among clinical sciences students as compared to preclinical sciences students. Pharyngeal colonization by Haemophilus influenzae was significantly higher among clinical sciences students as compared to preclinical sciences students. The pharyngeal colonization by beta-hemolytic streptococci (nongroup A) was higher among preclinical sciences students than clinical sciences students. CONCLUSION: The nasal colonization by S. aureus and MRSA was higher among clinical sciences students. Pharyngeal colonization by potential bacterial pathogens was higher among clinical sciences students than preclinical students. Periodic screening of MRSA and potential throat pathogens of clinical sciences students and may reduce the incidences of nosocomial transmission of pathogens.