BackgroundMethicillin resistant Staphylococcus aureus (MRSA) is a major human pathogen associated with nosocomial and community infections. Panton Valentine leukocidin (PVL) is considered one of the important virulence factors of S. aureus responsible for destruction of white blood cells, necrosis and apoptosis and as a marker of community acquired MRSA. This study was aimed to determine the prevalence of PVL genes among MRSA isolates and to check the reliability of PVL as marker of community acquired MRSA isolates from Western Nepal.MethodsA total of 400 strains of S. aureus were collected from clinical specimens and various units (Operation Theater, Intensive Care Units) of the hospital and 139 of these had been confirmed as MRSA by previous study. Multiplex PCR was used to detect mecA and PVL genes. Clinical data as well as antimicrobial susceptibility data was analyzed and compared among PVL positive and negative MRSA isolates.ResultsOut of 139 MRSA isolates, 79 (56.8 %) were PVL positive. The majority of the community acquired MRSA (90.4 %) were PVL positive (Positive predictive value: 94.9 % and negative predictive value: 86.6 %), while PVL was detected only in 4 (7.1 %) hospital associated MRSA strains. None of the MRSA isolates from hospital environment was found positive for the PVL genes. The majority of the PVL positive strains (75.5 %) were isolated from pus samples. Antibiotic resistance among PVL negative MRSA isolates was found higher as compared to PVL positive MRSA.ConclusionOur study showed high prevalence of PVL among community acquired MRSA isolates. Absence of PVL among MRSA isolates from hospital environment indicates its poor association with hospital acquired MRSA and therefore, PVL may be used a marker for community acquired MRSA. This is first study from Nepal, to test PVL among MRSA isolates from hospital environment.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-016-1531-1) contains supplementary material, which is available to authorized users.

BackgroundObjects 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.MethodsA 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.ResultsA 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.ConclusionsHigh 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.

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.

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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.