The olfactory test administered to patients at the Connecticut Chemosensory Clinical Research Center combines stability of outcome with sensitivity to variables known to affect olfaction (age, sex). The test, which pairs an odor threshold component with an odor identification component, readily resolves differences in function between patients and controls. It reveals differences in the distribution of functioning for various probable causes (nasal/sinus disease, postupper respiratory infection, and head trauma), proves sensitive to improvements in function caused by therapeutic intervention (ethmoidectomy, steroid administration for nasal/sinus disease), and correlates with objective signs of nasal/sinus disease (visual exam, x-ray). The two components of the test agree well, though the odor identification component seems somewhat more sensitive than the threshold component as currently designed.

Context Exposure to ozone and particulate matter of 2.5 µm or less (PM 2.5 ) in air at levels above current US Environmental Protection Agency (EPA) standards is a risk factor for respiratory symptoms in children with asthma.Objective To examine simultaneous effects of ozone and PM 2.5 at levels below EPA standards on daily respiratory symptoms and rescue medication use among children with asthma.Design, Setting, and Participants Daily respiratory symptoms and medication use were examined prospectively for 271 children younger than 12 years with physician-diagnosed, active asthma residing in southern New England. Exposure to ambient concentrations of ozone and PM 2.5 from April 1 through September 30, 2001, was assessed using ozone (peak 1-hour and 8-hour) and 24-hour PM 2.5 . Logistic regression analyses using generalized estimating equations were performed separately for maintenance medication users (n = 130) and nonusers (n = 141). Associations between pollutants (adjusted for temperature, controlling for same-and previous-day levels) and respiratory symptoms and use of rescue medication were evaluated. Main Outcome MeasuresRespiratory symptoms and rescue medication use recorded on calendars by subjects' mothers.Results Mean (SD) levels were 59 ( 19) ppb (1-hour average) and 51 ( 16) ppb (8hour average) for ozone and 13 (8) µg/m 3 for PM 2.5 . In copollutant models, ozone level but not PM 2.5 was significantly associated with respiratory symptoms and rescue medication use among children using maintenance medication; a 50-ppb increase in 1-hour ozone was associated with increased likelihood of wheeze (by 35%) and chest tightness (by 47%). The highest levels of ozone (1-hour or 8-hour averages) were associated with increased shortness of breath and rescue medication use. No significant, exposure-dependent associations were observed for any outcome by any pollutant among children who did not use maintenance medication. ConclusionAsthmatic children using maintenance medication are particularly vulnerable to ozone, controlling for exposure to fine particles, at levels below EPA standards.

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.

Competitive interactions between bacteria differ by number and species present; thus, vaccination and treatment strategies may alter nasopharyngeal flora and disease susceptibility.