In this investigation, exposure to duodenoscopes with bacterial contamination was associated with apparent transmission of NDM-producing E coli among patients at 1 hospital. Bacterial contamination of duodenoscopes appeared to persist despite the absence of recognized reprocessing lapses. Facilities should be aware of the potential for transmission of bacteria including antimicrobial-resistant organisms via this route and should conduct regular reviews of their duodenoscope reprocessing procedures to ensure optimal manual cleaning and disinfection.

Streptococcus pneumoniae asymptomatically colonizes the upper respiratory tract of children and is a frequent cause of otitis media. Patterns of microbial colonization likely influence S. pneumoniae colonization and otitis media susceptibility. This study compared microbial communities in children with and without otitis media. Nasal swabs and clinical and demographic data were collected in a cross-sectional study of Philadelphia, PA, children (6 to 78 months) (n = 108) during the 2008-2009 winter respiratory virus season. Swabs were cultured for S. pneumoniae. DNA was extracted from the swabs; 16S rRNA gene hypervariable regions (V1 and V2) were PCR amplified and sequenced by Roche/454 Life Sciences pyrosequencing. Microbial communities were described using the Shannon diversity and evenness indices. Principal component analysis (PCA) was used to group microbial community taxa into four factors representing correlated taxa. Of 108 children, 47 (44%) were colonized by S. pneumoniae, and 25 (23%) were diagnosed with otitis media. Microbial communities with S. pneumoniae were significantly less diverse and less even. Two PCA factors were associated with a decreased risk of pneumococcal colonization and otitis media, as follows: one factor included potentially protective flora (Corynebacterium and Dolosigranulum), and the other factor included Propionibacterium, Lactococcus, and Staphylococcus. The remaining two PCA factors were associated with an increased risk of otitis media. One factor included Haemophilus, and the final factor included Actinomyces, Rothia, Neisseria, and Veillonella. Generally, these taxa are not considered otitis media pathogens but may be important in the causal pathway. Increased understanding of upper respiratory tract microbial communities will contribute to the development of otitis media treatment and prevention strategies.

ABSTRACTThe composition of the upper respiratory tract microbial community may influence the risk for colonization by the acute otitis media (AOM) pathogensStreptococcus pneumoniae,Haemophilus influenzae, andMoraxella catarrhalis. We used culture-independent methods to describe upper respiratory tract microbial communities in healthy children and children with upper respiratory tract infection with and without concurrent AOM. Nasal swabs and data were collected in a cross-sectional study of 240 children between 6 months and 3 years of age. Swabs were cultured forS. pneumoniae, and real-time PCR was used to identifyS. pneumoniae,H. influenzae, andM. catarrhalis. The V1-V2 16S rRNA gene regions were sequenced using 454 pyrosequencing. Microbial communities were described using a taxon-based approach. Colonization byS. pneumoniae,H. influenzae, andM. catarrhaliswas associated with lower levels of diversity in upper respiratory tract flora. We identified commensal taxa that were negatively associated with colonization by each AOM bacterial pathogen and with AOM. The balance of these relationships differed according to the colonizing AOM pathogen and history of antibiotic use. Children with antibiotic use in the past 6 months and a greater abundance of taxa, includingLactococcusandPropionibacterium, were less likely to have AOM than healthy children (odds ratio [OR], 0.46; 95% confidence interval [CI], 0.25 to 0.85). Children with no antibiotic use in the past 6 months, a low abundance ofStreptococcusandHaemophilus, and a high abundance ofCorynebacteriumandDolosigranulumwere less likely to have AOM (OR, 0.51; 95% CI, 0.31 to 0.83). An increased understanding of polymicrobial interactions will facilitate the development of effective AOM prevention strategies.

Summary Nontyphoidal salmonella is estimated to be the most common bacterial cause of foodborne illness in the United States, causing an estimated one million domestically-acquired foodborne illnesses annually. Recent, large outbreaks have highlighted the importance of ground beef as an important source of multidrug resistant salmonella. We analysed the epidemiology of salmonellosis outbreaks that were attributed to beef in the United States reported to the Centers for Disease Control and Prevention (CDC) from 1973 through 2011. During 1973–2011, of the 1965 outbreaks of salmonella where a food vehicle was implicated, 96 were attributed to beef, accounting for 3684 illnesses. We observed a shift in the type of beef implicated in salmonellosis outbreaks, from roast to ground beef. Delicatessen-style roast beef cooked in commercial processing establishments was the predominant type during the 1970s and early 1980s; regulations on cooking and processing essentially eliminated this problem by 1987. Ground beef emerged as an important vehicle in the 2000s; it was implicated in 17 (45%) of the 38 beef-attributed outbreaks reported during 2002–2011. Although this emergence was likely due in part to increased participation in CDC’s PulseNet, which was established in 1996, and proactive decisions by the United States Department of Agriculture’s Food Safety and Inspection Service, stronger measures are needed to decrease contamination of ground beef with salmonella.