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Background. Staphylococcus aureus is among the most important pathogens in today's hospital setting. Methods. The effects of sneezing on the airborne dispersal of S. aureus and other bacteria were assessed in 11 healthy nasal S. aureus carriers with experimentally induced rhinovirus colds. Airborne dispersal was studied by volumetric air sampling in 2 chamber sessions with and without histamine-induced sneezing. After 2 days of preexposure measurements, volunteers were inoculated with a rhinovirus and monitored for 14 days. Daily quantitative nasal- and skin-culture samples for bacteria and nasal-culture samples for rhinovirus were obtained, cold symptoms were assessed, and volunteer activities were recorded during sessions. Results. All participants developed a cold. Sneezing caused a 4.7-fold increase in the airborne dispersal of S. aureus, a 1.4-fold increase in coagulase-negative staphylococci (CoNS), and a 3.9-fold increase in other bacteria (P<.001). An additional 2.83 colony forming units (cfu) of S. aureus/m(3)/min, 3.24 cfu of CoNS/m(3)/min, and 474.61 cfu of other bacteria/m(3)/min were released per sneeze. Rhinovirus exposure did not change the frequency of sneezing or airborne dispersal. Having respiratory allergies increased the spread of S. aureus by 3.8-fold during sneezing sessions (P<.001). Conclusion. Nasal S. aureus carriers disperse a significant amount of S. aureus into the air by sneezing. Experimental colds do not alter bacterial dispersal, but respiratory allergies multiply the effect of dispersing S. aureus. Copyright © 2006 Infectious Diseases Society of America [ABSTRACT FROM AUTHOR]

Background: Central venous catheter-related infections are a significant medical problem. Improved preventive measures are needed.Objective: To ascertain 1) effectiveness of a second-generation antiseptic-coated catheter in the prevention of microbial colonization and infection; 2) safety and tolerability of this device; 3) microbiology of infected catheters; and 4) propensity for the development of antiseptic resistance.Design: Multicenter, randomized, double-blind, controlled trial.Setting: 9 university-affiliated medical centers.Patients: 780 patients in intensive care units who required central venous catheterization.Intervention: Patients received either a standard catheter or a catheter coated with chlorhexidine and silver sulfadiazine.Measurements: The authors assessed catheter colonization and catheter-related infection, characterized microbes by molecular typing, and determined their susceptibility to antiseptics. Patient tolerance of the catheter was monitored.Results: Patients with the 2 types of catheters had similar demographic features, clinical interventions, laboratory values, and risk factors for infection. Antiseptic catheters were less likely to be colonized at the time of removal compared with control catheters (13.3 vs. 24.1 colonized catheters per 1000 catheter-days; P < 0.01). The center-stratified Cox regression hazard ratio for colonization controlling for sampling design and potentially confounding variables was 0.45 (95% CI, 0.25 to 0.78). The rate of definitive catheter-related bloodstream infection was 1.24 per 1000 catheter-days (CI, 0.26 to 3.62 per 1000 catheter-days) for the control group versus 0.42 per 1000 catheter-days (CI, 0.01 to 2.34 per 1000 catheter-days) for the antiseptic catheter group (P = 0.6). Coagulase-negative staphylococci and other gram-positive organisms were the most frequent microbes to colonize catheters. Noninfectious adverse events were similar in both groups. Antiseptic susceptibility was similar for microbes recovered from either group.Limitations: The antiseptic catheter was not compared with an antibiotic-coated catheter, and no conclusion can be made regarding its effect on bloodstream infection.Conclusions: The second-generation chlorhexidine-silver sulfadiazine catheter is well tolerated. Antiseptic coating appears to reduce microbial colonization of the catheter compared with an uncoated catheter. [ABSTRACT FROM AUTHOR]