Emergence and spread of a human-transmissible multidrug-resistant nontuberculous mycobacterium.

Lung infections with Mycobacterium abscessus, a species of multidrug-resistant nontuberculous mycobacteria, are emerging as an important global threat to individuals with cystic fibrosis (CF), in whom M. abscessus accelerates inflammatory lung damage, leading to increased morbidity and mortality. Previously, M. abscessus was thought to be independently acquired by susceptible individuals from the environment. However, using whole-genome analysis of a global collection of clinical isolates, we show that the majority of M. abscessus infections are acquired through transmission, potentially via fomites and aerosols, of recently emerged dominant circulating clones that have spread globally. We demonstrate that these clones are associated with worse clinical outcomes, show increased virulence in cell-based and mouse infection models, and thus represent an urgent international infection challenge.

Acidovorax oryzae catheter-associated bloodstream infection.

Acidovorax oryzae is a bacterium that has never before been reported as pathogenic in human subjects. Here we describe the first case of a successfully treated A. oryzae catheter-associated bloodstream infection in an immunocompetent patient prior to heart transplantation.

Panton-Valentine Leukocidin-positive Staphylococcus aureus: a potentially significant pathogen in cystic fibrosis.

Staphylococcus aureus is an important pathogen within the context of cystic fibrosis lung disease. Case reports have identified a strong association between the toxin Panton-Valentine Leukocidin (PVL) and lethal necrotizing pneumonia in healthy immunocompetent patients. PVL+ strains of Staphylococcus aureus have also been identified in patients with cystic fibrosis. We describe a further case of pneumonia in a patient with cystic fibrosis, and outline potential transmission of the organism from healthy family members to this patient. We review the evidence regarding the pathogenicity of PVL toxin with a special reference to patients with cystic fibrosis. We outline current concerns regarding the potential transmission of the organism and possible treatment strategies.

Influenza aerosols in UK hospitals during the H1N1 (2009) pandemic--the risk of aerosol generation during medical procedures.

BACKGROUND: Nosocomial infection of health-care workers (HCWs) during outbreaks of respiratory infections (e.g. Influenza A H1N1 (2009)) is a significant concern for public health policy makers. World Health Organization (WHO)-defined 'aerosol generating procedures' (AGPs) are thought to increase the risk of aerosol transmission to HCWs, but there are presently insufficient data to quantify risk accurately or establish a hierarchy of risk-prone procedures. METHODOLOGY/PRINCIPAL FINDINGS: This study measured the amount of H1N1 (2009) RNA in aerosols in the vicinity of H1N1 positive patients undergoing AGPs to help quantify the potential risk of transmission to HCWs. There were 99 sampling occasions (windows) producing a total of 198 May stages for analysis in the size ranges 0.86-7.3 µm. Considering stages 2 (4-7.3 µm) and 3 (0.86-4 µm) as comprising one sample, viral RNA was detected in 14 (14.1%) air samples from 10 (25.6%) patients. Twenty three air samples were collected while potential AGPs were being performed of which 6 (26.1%) contained viral RNA; in contrast, 76 May samples were collected when no WHO 2009 defined AGP was being performed of which 8 (10.5%) contained viral RNA (unadjusted OR = 2.84 (95% CI 1.11-7.24) adjusted OR = 4.31 (0.83-22.5)). CONCLUSIONS/SIGNIFICANCE: With our small sample size we found that AGPs do not significantly increase the probability of sampling an H1N1 (2009) positive aerosol (OR (95% CI) = 4.31 (0.83-22.5). Although the probability of detecting positive H1N1 (2009) positive aerosols when performing various AGPs on intensive care patients above the baseline rate (i.e. in the absence of AGPs) did not reach significance, there was a trend towards hierarchy of AGPs, placing bronchoscopy and respiratory and airway suctioning above baseline (background) values. Further, larger studies are required but these preliminary findings may be of benefit to infection control teams.

Sternal wound infections: improvements made to reduce rates.

Wound infections from surgical sites account for 15% of all healthcare-associated infections (National Institute for Health and Clinical Excellence (NICE), 2008). There is evidence that the care provided before and after the operation is paramount to minimize the risk of surgical site infection. Sternal wound infections lengthen hospital stays (or prompt readmission) and carry a high mortality rate. In August 2009 a Manchester Hospital discovered a cluster of three patients with sternal wound infections. A review of clinical data for patients having cardiac surgery from 1 December 2008 and 9 October 2009 revealed an increased incidence of patients with sternal wound infections. The data did not reveal a significant problem, but one that should be kept under observation. During the investigation no single pathogen had been identified as responsible and no obvious source of environmental infection was identified. Implementing additional infection prevention and control practices helped the hospital team to improve the care given to patients. A host of factors, ranging from providing more information on wound care to patients, improving audit scores, and adhering to NICE guidelines, contributed to the reduction in this type of surgical site infection.

Prospective surveillance for Pseudomonas aeruginosa cross-infection at a cystic fibrosis center.

We have performed a 4-year prospective surveillance for Pseudomonas aeruginosa cross-infection at a large regional adult cystic fibrosis center. Despite purpose-built facilities in a new building and the practice of strict hygiene, P. aeruginosa cross-infection has continued. In contrast, individuals segregated from the cohort of patients with chronic P. aeruginosa infection but who attend the same center have not acquired infection with transmissible P. aeruginosa strains. Simple infection control measures alone do not prevent the spread of transmissible P. aeruginosa strains between individuals with cystic fibrosis. However, in our clinic patient segregation effectively controlled spread of such strains.