The survival of influenza A(H1N1)pdm09 virus on 4 household surfaces.

We investigated the survival of a pandemic strain of influenza A H1N1 on a variety of common household surfaces where multiple samples were taken from 4 types of common household fomite at 7 time points. Results showed that influenza A H1N1sw virus particles remained infectious for 48 hours on a wooden surface, for 24 hours on stainless steel and plastic surfaces, and for 8 hours on a cloth surface, although virus recovery from the cloth may have been suboptimal. Our results suggest that pandemic influenza A H1N1 can survive on common household fomites for extended periods of time, and that good hand hygiene and regular disinfection of commonly touched surfaces should be practiced during the influenza season to help reduce transmission.

Proteolytic activity by multiple bacterial species isolated from chronic venous leg ulcers degrades matrix substrates.

BACKGROUND: A major feature of chronic wounds is the loss of tissue, with the exposure of dermal components preventing primary closure and leading to bacterial colonization. Bacterial colonization has been proposed as one of the common underlying pathologies present in chronic wounds. The objective of this exploratory study was to identify bacteria cultured from chronic venous leg ulcers and test for proteolytic activity that degrades matrix substrates. METHOD: Bacteria were isolated, cultured, and identified from six subjects (average age = 62.8 years) over 2-10 months under an approved protocol using swabs and microbiological culture media. Proteolytic activity against (a) gelatin, (b) an elastin substrate, and (c) a serine/trypsin-sensitive substrate was determined using a colorimetric plate assay with an ELISA plate reader and zymography. RESULTS: We identified 13 bacteria that expressed proteolytic activity against one or more of the tested substrates. Of these, six were Gram-positive (Staphylococcus aureus, Enterococcus faecalis, Staphylococcus epidermidis, Streptococcus agalactiae, Corynebacterium, and Streptococcus bovis) and seven were Gram-negative (Pseudomonas aeruginosa, Escherichia coli, Proteus mirabilis, Morganella morganii, Klebsiella pneumoniae, Bacteroides fragilis, and Serratia marcescens) organisms. Two of these, S. aureus and P. aeruginosa, are recognized wound pathogens. CONCLUSIONS: Multiple bacteria species isolated from colonized venous leg ulcers have the capacity to secrete proteases capable of degrading components of the extracellular matrix important for wound healing. Matrix degradation by bacteria may contribute to delays in tissue deposition and repair, suggesting that treatment of chronic wounds should include appropriate management of colonizing bacteria.

Outbreak of Klebsiella pneumoniae producing a new carbapenem-hydrolyzing class A beta-lactamase, KPC-3, in a New York Medical Center.

From April 2000 to April 2001, 24 patients in intensive care units at Tisch Hospital, New York, N.Y., were infected or colonized by carbapenem-resistant Klebsiella pneumoniae. Pulsed-field gel electrophoresis identified a predominant outbreak strain, but other resistant strains were also recovered. Three representatives of the outbreak strain from separate patients were studied in detail. All were resistant or had reduced susceptibility to imipenem, meropenem, ceftazidime, piperacillin-tazobactam, and gentamicin but remained fully susceptible to tetracycline. PCR amplified a blaKPC allele encoding a novel variant, KPC-3, with a His(272)-->Tyr substitution not found in KPC-2; other carbapenemase genes were absent. In the outbreak strain, KPC-3 was encoded by a 75-kb plasmid, which was transferred in vitro by electroporation and conjugation. The isolates lacked the OmpK35 porin but expressed OmpK36, implying reduced permeability as a cofactor in resistance. This is the third KPC carbapenem-hydrolyzing beta-lactamase variant to have been reported in members of the Enterobacteriaceae, with others reported from the East Coast of the United States. Although producers of these enzymes remain rare, the progress of this enzyme group merits monitoring.

Increasing antibiotic resistance of streptococcus species in New York City.

OBJECTIVE: Streptococcus species are common pathogens in head and neck infections and are leading causes of morbidity and mortality. Emerging penicillin-resistant streptococcal pathogens have shifted empirical antibiotic therapy in favor of valuable alternatives, including erythromycin and clindamycin. This study was undertaken to determine the magnitude of antimicrobial resistance to these antibiotics. STUDY DESIGN: Retrospective review. METHODS: A retrospective study of two streptococcal species isolates, Streptococcus pyogenes (163 specimens) and Streptococcus pneumoniae (164 specimens), collected between January 1, 2001 and January 1, 2002 at two academic institutions. The antibiotic susceptibility patterns were analyzed for penicillin, erythromycin, and clindamycin according to the National Committee for Clinical Laboratory Standards. RESULTS: Fourteen percent to 34% of S. pyogenes isolates were erythromycin-resistant, and 0% to 28% were clindamycin-resistant. None of the S. pyogenes isolates were resistant to penicillin. Of the S. pneumoniae isolates, 33% to 50% were resistant to erythromycin, and 18% to 33% were resistant to clindamycin. The penicillin resistance levels for S. pneumoniae were 0% to 45%. CONCLUSIONS: Our antimicrobial resistance levels for S. pyogenes and S. pneumoniae significantly exceeded national and worldwide levels of erythromycin and clindamycin resistance. With a diverse population of over 8 million residents and high physician supply, our model is a microcosm for the study of antimicrobial use and susceptibility patterns and of clinical failure.

Isolation of fungi by standard laboratory methods in patients with chronic rhinosinusitis.

OBJECTIVES/HYPOTHESIS: Allergic fungal sinusitis and the role of fungi in the pathogenesis of chronic rhinosinusitis are topics of interest and controversy in rhinology. The classification of chronic rhinosinusitis as either a bacterial infection or an allergic (eosinophilic) reaction to fungi has significant implications for treatment of this disease process. We designed a study to determine whether standard isolation techniques, as employed in a university hospital mycology laboratory, could isolate and identify fungi in the intraoperative specimens from patients undergoing functional endoscopic sinus surgery for chronic rhinosinusitis. STUDY DESIGN: Forty-five random patients with a diagnosis of chronic rhinosinusitis by clinical and computed tomography criteria underwent endoscopic sinus surgery during 2001, performed by two senior surgeons (J.B.J., R.A.L.). Specimens of mucin, sinus secretions, and/or tissue were obtained intraoperatively and sent to the New York University Medical Center (New York, NY) mycology laboratory for isolation and identification of fungi. METHODS: Specimens were treated with Sputolysin and chloramphenicol; plated on Sabouraud, ChromAgar/Candida, Mycosel, and Niger seed agar plates; and incubated at 30 degrees C (or 37 degrees C) for up to 1 month. RESULTS: We were able to demonstrate the presence of fungi in 56% of intraoperative specimens obtained from patients undergoing surgery for chronic rhinosinusitis. CONCLUSIONS: Using a standard hospital mycology laboratory protocol, which is relatively inexpensive and readily available, fungus can be isolated from a majority of patients undergoing functional endoscopic sinus surgery for chronic rhinosinusitis. Educational statement: Discuss the possible role of fungus in chronic rhinosinusitis and evaluate the efficacy of documenting the presence of fungus in a routine fashion to encourage clinically relevant directed treatments.)