Associations of air pollution and greenness with the nasal microbiota of healthy infants: A longitudinal study

Greenspace and human microbiota: A systematic review

BACKGROUND

Potential effect of greenspace exposure on human microbiota have been explored by a number of observational and interventional studies, but the results remained mixed. We comprehensively synthesized these studies by performing a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

METHODS

Comprehensive literature searches in three international databases (PubMed, Embase, and Web of Science) and three Chinese databases (China National Knowledge Infrastructure, Wanfang, and China Biology Medicine disc) were conducted from inception to November 1, 2023. Observational and interventional studies that evaluated associations between greenspace exposure and human microbiota at different anatomical sites were included. Studies were assessed using the National Toxicology Program's office of Health Assessment and Translation risk of bias tool and certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation framework. Two authors independently performed study selection, data extraction, and risk of bias assessment, and evidence grading. Study results were synthesized descriptively.

RESULTS

Twenty studies, including 11 observational studies and 9 interventional studies, were finally included into the systematic review. The microbiota of the included studies was from gut (n = 13), skin (n = 10), oral cavity (n = 5), nasal cavity (n = 5) and eyes (n = 1). The majority of studies reported the associations of greenspace exposure with increased diversity (e.g., richness and Shannon index) and/or altered overall composition of human gut (n = 12) and skin microbiota (n = 8), with increases in the relative abundance of probiotics (e.g., Ruminococcaceae) and decreases in the relative abundance of pathogens (e.g., Streptococcus and Escherichia/Shigella). Due to limited number of studies, evidence concerning greenspace and oral, nasal, and ocular microbiota were still inconclusive.

CONCLUSION

The current evidence suggests that greenspace exposure may diversify gut and skin microbiota and alter their composition to healthier profiles. These findings would be helpful in uncovering the potential mechanisms underlying greenspace and human health and in promoting a healthier profile of human microbiota.

Human nasal microbiota shifts in healthy and chronic respiratory disease conditions

BACKGROUND

An increasing number of studies investigate various human microbiotas and their roles in the development of diseases, maintenance of health states, and balanced signaling towards the brain. Current data demonstrate that the nasal microbiota contains a unique and highly variable array of commensal bacteria and opportunistic pathogens. However, we need to understand how to harness current knowledge, enrich nasal microbiota with beneficial microorganisms, and prevent pathogenic developments.

RESULTS

In this study, we have obtained nasal, nasopharyngeal, and bronchoalveolar lavage fluid samples from healthy volunteers and patients suffering from chronic respiratory tract diseases for full-length 16 S rRNA sequencing analysis using Oxford Nanopore Technologies. Demographic and clinical data were collected simultaneously. The microbiome analysis of 97 people from Lithuania suffering from chronic inflammatory respiratory tract disease and healthy volunteers revealed that the human nasal microbiome represents the microbiome of the upper airways well.

CONCLUSIONS

The nasal microbiota of patients was enriched with opportunistic pathogens, which could be used as indicators of respiratory tract conditions. In addition, we observed that a healthy human nasal microbiome contained several plant- and bee-associated species, suggesting the possibility of enriching human nasal microbiota via such exposures when needed. These candidate probiotics should be investigated for their modulating effects on airway and lung epithelia, immunogenic properties, neurotransmitter content, and roles in maintaining respiratory health and nose-brain interrelationships.

PM2.5 Causes Increased Bacterial Invasion by Affecting HBD1 Expression in the Lung

Our research addresses the critical environmental issue of a fine particulate matter (PM2.5), focusing on its association with the increased infection risks. We explored the influence of PM2.5 on human beta-defensin 1 (HBD1), an essential peptide in mucosal immunity found in the airway epithelium. Using C57BL/6J mice and human bronchial epithelial cells (HBE), we examined the effects of PM2.5 exposure followed by Pseudomonas aeruginosa (P. aeruginosa) infection on HBD1 expression at both mRNA and protein levels. The study revealed that PM2.5's toxicity to epithelial cells and animals varies with time and concentration. Notably, HBE cells exposed to PM2.5 and P. aeruginosa showed increased bacterial invasion and decreased HBD1 expression compared to the cells exposed to P. aeruginosa alone. Similarly, mice studies indicated that combined exposure to PM2.5 and P. aeruginosa significantly reduced survival rates and increased bacterial invasion. These harmful effects, however, were alleviated by administering exogenous HBD1. Furthermore, our findings highlight the activation of MAPK and NF-κB pathways following PM2.5 exposure. Inhibiting these pathways effectively increased HBD1 expression and diminished bacterial invasion. In summary, our study establishes that PM2.5 exposure intensifies P. aeruginosa invasion in both HBE cells and mouse models, primarily by suppressing HBD1 expression. This effect can be counteracted with exogenous HBD1, with the downregulation mechanism involving the MAPK and NF-κB pathways. Our study endeavors to elucidate the pathogenesis of lung infections associated with PM2.5 exposure, providing a novel theoretical basis for the development of prevention and treatment strategies, with substantial clinical significance.

Association of antenatal and early childhood air pollution and greenspace exposures with respiratory pathogen upper airway acquisitions and respiratory health outcomes

The association of air pollution and greenspace with respiratory pathogen acquisition and respiratory health was investigated in a community-based birth-cohort of 158 Australian children. Weekly nasal swabs and daily symptom-diaries were collected for 2-years, with annual reviews from ages 3-7-years. Annual exposure to fine-particulate-matter (PM2.5), nitrogen-dioxide (NO2), and normalised-difference-vegetation-index (NDVI) was estimated for pregnancy and the first 2-years-of-life. We examined rhinovirus, any respiratory virus, Streptococcus pneumoniae, Moraxella catarrhalis, and Haemophilus influenzae detections in the first 3-months-of-life, age at initial pathogen detection, wheezing in the first 2-years, and asthma at ages 5-7-years. Our findings suggest that higher NDVI was associated with fewer viral and M. catarrhalis detections in the first 3-months, while increased PM2.5 and NO2 were linked to earlier symptomatic rhinovirus and H. influenzae detections, respectively. However, no associations were observed with wheezing or asthma. Early-life exposure to air pollution and greenspace may influence early-life respiratory pathogen acquisition and illness.  .

Greenness and chronic respiratory health issues: a systematic review and meta-analysis

Introduction

The number of chronic respiratory disease (CRD) individuals worldwide has been continuously increasing. Numerous studies have shown that greenness can improve chronic respiratory health issues through different mechanisms, with inconsistent evidence. By quantitatively summarizing existing studies, our purpose is to determine the connection between greenness exposure and various chronic respiratory health.

Methods

We conducted a comprehensive search on PubMed, EMBASE, and Web of Science core databases to identify relevant studies on the correlation between greenness exposure and chronic respiratory health issues. Studies published up to January 2023 were included in the search. The study used the most frequent indicator (normalized difference vegetation index [NDVI]) as the definition of greenness exposure.

Results

We finally identified 35 studies for meta-analysis. We calculated pooled effects across studies using a random-effects model and conducted a subgroup analysis by age and buffer zones to discuss the effects on chronic respiratory health issues. This study showed that 0.1 increments in NDVI were significantly related to lower rates of asthma incidence, lung cancer incidence, and chronic obstructive pulmonary disease (COPD) mortality risk; the pooled RRs were 0.92 (95% CI: 0.85-0.98), 0.62 (95% CI: 0.40-0.95), and 0.95 (95% CI: 0.92- 0.99), respectively. For the age subgroup, the higher greenness exposure level was related to the incidence rate of asthma among teenagers aged 13-18years (RR: 0.91; 95% CI: 0.83-0.99). For the buffer subgroup, a positive relationship with greenness exposure and asthma incidence/prevalence at 200-300m and 800- 1000m buffers, as well as the COPD mortality at 800-1000m buffer, the pooled RRs were 0.92 (95% CI: 0.86-0.98), 0.87 (95% CI: 0.81-0.93), and 0.93 (95% CI: 0.88- 0.98), respectively. Evidence of publication bias was not detected in this study.

Discussion

Our study is the first global meta-analysis between greenness and various CRDs to report an inverse association. Further research is needed in order to determine the effect of greenness exposure on different CRDs. Therefore, when planning for green development, more consideration must be given to public health and green management as intervention measures.

https://www.crd.york.ac.uk/PROSPEROFILES/384029_STRATEGY_20230116.pdf.

The Role of Indoor Microbiome and Metabolites in Shaping Children's Nasal and Oral Microbiota: A Pilot Multi-Omic Analysis

Maintaining a diverse and well-balanced nasal and oral microbiota is vital for human health. However, the impact of indoor microbiome and metabolites on nasal and oral microbiota remains largely unknown. Fifty-six children in Shanghai were surveyed to complete a questionnaire about their personal and environmental characteristics. The indoor microbiome and metabolites from vacuumed indoor dust were profiled via shotgun metagenomics and untargeted liquid chromatography-mass spectrometry (LC-MS). The nasal and oral microbiota in children was characterized using full-length 16S rRNA sequencing from PacBio. Associations between personal/environmental characteristics and the nasal/oral microbiota were calculated using PERMANOVA and regression analyses. We identified 6247, 431, and 342 microbial species in the indoor dust, nasal, and oral cavities, respectively. The overall nasal and oral microbial composition showed significant associations with environmental tobacco smoke (ETS) exposure during pregnancy and early childhood (p = 0.005 and 0.03, respectively), and the abundance of total indoor flavonoids and two mycotoxins (deoxynivalenol and nivalenol) (p = 0.01, 0.02, and 0.03, respectively). Notably, the abundance of several flavonoids, such as baicalein, eupatilin, isoliquiritigenin, tangeritin, and hesperidin, showed positive correlations with alpha diversity and the abundance of protective microbial taxa in nasal and oral cavities (p < 0.02), suggesting their potential beneficial roles in promoting nasal/oral health. Conversely, high carbohydrate/fat food intake and ETS exposure diminished protective microorganisms while augmenting risky microorganisms in the nasal/oral cavities. Further, potential microbial transfer was observed from the indoor environment to the childhood oral cavity (Moraxella catarrhalis, Streptococcus mitis, and Streptococcus salivarius), which could potentially increase virulence factors related to adherence and immune modulation and vancomycin resistance genes in children. This is the first study to reveal the association between the indoor microbiome/metabolites and nasal/oral microbiota using multi-omic approaches. These findings reveal potential protective and risk factors related to the indoor microbial environment.

The association between nasal mucosa bacteria and serum metals in children with nasal diseases

Allergic rhinitis (AR) and adenoid hypertrophy (AH) are common nasal diseases in children. Studies have shown that heavy metals are environmental risk factors for nasal diseases, and the pathogenic mechanisms may be related to dysregulation of nasal mucosal microbiota. However, it is unclear how heavy metal exposure relates to the nasal mucosal microbiota in nasal diseases. Therefore, we explored serum metal exposure levels and nasal mucosal microbiota composition in children with different nasal disease, and further studied the potential correlation between metal exposure and disease-related taxa. There were 64 children recruited for this study. The 23 metals concentrations in serum were measured by inductively coupled plasma mass spectrometry, and nasal mucosal bacteria was identified by 16S rRNA sequencing. Nasal diseases (AR and AH) in children were associated with alterations in the abundance and diversity of the nasal mucosal microbiota. The nasal microbiota of children with AR showed lower diversity, while the microbiota of children with AH showed higher diversity. Linear discriminant analysis Effect Size showed 108 differentially abundant taxa between AR and control groups, 35 differentially abundant taxa among large adenoid, moderate adenoid and small adenoid groups. The serum zinc concentration was negatively correlated with Pielou's eveness index and Simpson's Index in children classified by adenoid size. The spearman correlation analysis showed that multiple disease-related taxa were closely associated with metal concentrations in serum. Our findings may support a link between metal exposure and the diversity and composition of nasal bacteria in children with nasal disease, which present new evidence for the effects of metals on children health.

Association between Residential Greenness and Human Microbiota: Evidence from Multiple Countries

BACKGROUND

Greenness, referring to a measurement of the density of vegetated land (e.g., gardens, parks, grasslands), has been linked with many human health outcomes. However, the evidence on greenness exposure and human microbiota remains limited, inconclusive, drawn from specific regions, and based on only modest sample size.

OBJECTIVES

We aimed to study the association between greenness exposure and human microbial diversity and composition in a large sample across 34 countries and regions.

METHODS

We explored associations between residential greenness and human microbial alpha-diversity, composition, and genus abundance using data from 34 countries. Greenness exposure was assessed using the normalized difference vegetation index and the enhanced vegetation index mean values in the month before sampling. We used linear regression models to estimate the association between greenness and microbial alpha-diversity and tested the effect modification of age, sex, climate zone, and pet ownership of participants. Differences in microbial composition were tested by permutational multivariate analysis of variance based on Bray-Curtis distance and differential taxa were detected using the DESeq2 R package between two greenness exposure groups split by median values of greenness.

RESULTS

We found that higher greenness was significantly associated with greater richness levels in the palm and gut microbiota but decreased evenness in the gut microbiota. Pet ownership and climate zone modified some associations between greenness and alpha-diversity. Palm and gut microbial composition at the genus level also varied by greenness. Higher abundances of the genera Lactobacillus and Bifidobacterium, and lower abundances of the genera Anaerotruncus and Streptococcus, were observed in people with higher greenness levels.

DISCUSSION

These findings suggest that residential greenness was associated with microbial richness and composition in the human skin and gut samples, collected across different geographic contexts. Future studies may validate the observed associations and determine whether they correspond to improvements in human health. https://doi.org/10.1289/EHP12186.

Air pollution-associated shifts in the human airway microbiome and exposure-associated molecular events

Publications addressing air pollution-induced human respiratory microbiome shifts are reviewed in this article. The healthy respiratory microbiota is characterized by a low density of bacteria, fungi and viruses with high diversity, and usually consists of Bacteroidetes, Firmicutes, Proteobacteria, Actinobacteria, Fusobacteria, viruses and fungi. The air's microbiome is highly dependent on air pollution levels and is directly reflected within the human respiratory microbiome. In addition, pollutants indirectly modify the local environment in human respiratory organs by reducing antioxidant capacity, misbalancing proteolysis and modulating inflammation, all of which regulate local microbiomes. Improving air quality leads to more diverse and healthy microbiomes of the local air and, subsequently, residents' airways.

Ambient air pollution and infant health: a narrative review

The extensive evidence regarding the effects of ambient air pollution on child health is well documented, but limited review summarized their health effects during infancy. Symptoms or health conditions attributed to ambient air pollution in infancy could result in the progression of severe diseases during childhood. Here, we reviewed previous empirical epidemiological studies and/or reviews for evaluating the linkages between ambient air pollution and various infant outcomes including adverse birth outcomes, infant morbidity and mortality, early respiratory health, early allergic symptoms, early neurodevelopment, early infant growth and other relevant outcomes. Patterns of the associations varied by different pollutants (i.e., particles and gaseous pollutants), exposure periods (i.e., pregnancy and postpartum) and exposure lengths (i.e., long-term and short-term). Protection of infant health requires that paediatricians, researchers, and policy makers understand to what extent infants are affected by ambient air pollution, and a call for action is still necessary to reduce ambient air pollution.

The possible role of particulate matter on the respiratory microbiome: evidence from in vivo to clinical studies

Environmental pollution, which contains ambient particulate matter, has been shown to have a significant impact on human health and longevity over the past 30 years. Recent studies clearly showed that exposure to particulate matter directly caused adverse effects on the respiratory system via various mechanisms including the accumulation of free radical peroxidation, the imbalance of intercellular calcium regulation, and inflammation, resulting in respiratory diseases. Recent evidence showed the importance of the role of the respiratory microbiome on lung immunity and lung development. In addition, previous studies have confirmed that several chronic respiratory diseases were associated with an alteration in the respiratory microbiome. However, there is still a lack of knowledge with regard to the changes in the respiratory microbiome with regard to the role of particulate matter exposure in respiratory diseases. Therefore, this review aims to summarize and discuss all the in vivo to clinical evidence which investigated the effect of particulate matter exposure on the respiratory microbiome and respiratory diseases. Any contradictory findings are incorporated and discussed. A summary of all these pieces of evidence may offer an insight into a therapeutic approach for the respiratory diseases related to particulate matter exposure and respiratory microbiome.

Residential greenness and air pollution's association with nasal microbiota among asthmatic children

Both greenness and air pollution have widely been linked with asthma. However, the potential mechanism has rarely been investigated. This study aimed to identify the association between residential greenness and air pollution (fine particulate matter [PM_2.5]; nitrogen dioxide [NO₂]; ozone [O₃]) with nasal microbiota among asthmatic children during the recovery phase. The normalized difference vegetation index was used to assess the extent of residential greenness. Spatiotemporal air pollution variation was estimated using an integrated hybrid kriging-LUR with the XG-Boost algorithm. These exposures were measured in 250-m intervals for four incremental buffer ranges. Nasal microbiota was collected from 47 children during the recovery phase. A generalized additive model controlled for various covariates was applied to evaluate the exposure-outcome association. The lag-time effect of greenness and air pollution related to the nasal microbiota also was examined. A significant negative association was observed between short-term exposure to air pollution and nasal bacterial diversity, as a one-unit increment in PM_2.5 or O₃ significantly decreased the observed species (PM_2.5: -0.59, 95%CI -1.13, -0.05 and O₃: -0.93, 95%CI -1.54, -0.32) and species richness (PM_2.5: -0.64, 95%CI -1.25, -0.02 and O₃: -0.68, 95%CI -1.43, -0.07). Considering the lag-time effect, we found a significant positive association between greenness and both the observed species and species richness. In addition, we identified a significant negative association for all pollutants with the observed species richness. These findings add to the evidence base of the links between nasal microbiota and air pollution and greenness. This study establishes a foundation for future studies of how environmental exposure plays a role in nasal microbiota, which in turn may affect the development of asthma.

Associations of Air Pollution and Serum Biomarker Abnormalities in Individuals with Hemodialysis-Dependent Kidney Failure

BACKGROUND

Ambient particles with a median aerodynamic diameter of <2.5 µm (PM2.5) is a ubiquitous air pollutant with established adverse health consequences. While postulated to promote a systemic inflammatory response, limited studies have demonstrated changes in serum biomarkers related to PM2.5 exposure. We aim to examine associations between short-term PM2.5 exposure and commonly measured biomarkers known to be affected by inflammation among patients receiving maintenance in-center hemodialysis.

METHODS

We conducted a retrospective open cohort study from January 1, 2008, to December 31, 2014. Adult hemodialysis patients were identified from the United States Renal Data System and linked at the patient level to laboratory data from a large dialysis organization. Daily ambient PM2.5 was estimated on a 1-km grid and assigned to cohort patients based on the ZIP codes of dialysis clinics. Serum albumin, serum ferritin, transferrin saturation (TSAT), and serum hemoglobin were ascertained from the dialysis provider organization database. Mixed-effect models were used to assess the changes in biomarker levels associated with PM2.5 exposure.

RESULTS

The final cohort included 173,697 hemodialysis patients. Overall, the daily ZIP-level ambient PM2.5 averages were 8.4-8.5 µg/m3. A 10-µg/m3 increase in same-day ambient PM2.5 exposure was associated with higher relative risks of lower albumin (relative risk [RR], 1.01; 95% confidence interval [95% CI], 1.01 to 1.02) and lower hemoglobin (RR, 1.02; 95% CI, 1.01 to 1.03). Associations of same-day ambient PM2.5 exposure and higher ferritin and lower TSAT did not reach statistical significance.

CONCLUSIONS

Short-term PM2.5 exposure was associated with lower serum hemoglobin and albumin among patients receiving in-center hemodialysis. These findings lend support to the role of inflammation in PM2.5 exposure-outcome associations.

Greenspace and health outcomes in children and adolescents: A systematic review

An increasing body of evidence has linked greenspace and various health outcomes in children and adolescents, but the conclusions were inconsistent. For this review, we comprehensively summarized the measurement methods of greenspace, resultant health outcomes, and potential mechanisms from epidemiological studies in children and adolescents (aged ≤19 years). We searched for studies published and indexed in MEDLINE and EMBASE (via Ovid) up to April 11, 2022. There were a total of 9,291 studies identified with 140 articles from 28 countries finally assessed and included in this systematic review. Over 70% of the studies were conducted in highly urbanised countries/regions, but very limited research has been done in low-and middle-income countries and none in Africa. Measures of greenspace varied. Various health outcomes were reported, including protective effects of greenspace exposure on aspects of obesity/overweight, myopia, lung health, circulatory health, cognitive function, and general health in children and adolescents. The associations between greenspace exposure and other health outcomes were inconsistent, especially for respiratory health studies. We pooled odds ratios (OR) using random-effects meta-analysis for health outcomes of asthma (OR = 0.94, 95%CI: 0.84 to 1.06), allergic rhinitis (OR = 0.95; 95% CI: 0.73 to 1.25), and obesity/overweight (OR = 0.91, 95%CI: 0.84 to 0.98) with per 0.1 unit increase in normalized difference in vegetation index (NDVI). These associations have important implications for the assessment and management of urban environment and health in children and adolescents.

Deleterious Effect of Air Pollution on Human Microbial Community and Bacterial Flora: A Short Review

A balanced microbiota composition is requisite for normal physiological functions of the human body. However, several environmental factors such as air pollutants may perturb the human microbiota composition. It is noticeable that currently around 99% of the world's population is breathing polluted air. Air pollution's debilitating health impacts have been studied scrupulously, including in the human gut microbiota. Nevertheless, air pollution's impact on other microbiotas of the human body is less understood so far. In the present review, the authors have summarized and discussed recent studies' outcomes related to air pollution-driven microbiotas' dysbiosis (including oral, nasal, respiratory, gut, skin, and thyroid microbiotas) and its potential multi-organ health risks.

Mechanistic Insights into the Impact of Air Pollution on Pneumococcal Pathogenesis and Transmission

Streptococcus pneumoniae (the pneumococcus) is the leading cause of pneumonia and bacterial meningitis. A number of recent studies indicate an association between the incidence of pneumococcal disease and exposure to air pollution. Although the epidemiological evidence is substantial, the underlying mechanisms by which the various components of air pollution (particulate matter and gases such as NO2 and SO2) can increase susceptibility to pneumococcal infection are less well understood. In this review, we summarize the various effects air pollution components have on pneumococcal pathogenesis and transmission; exposure to air pollution can enhance host susceptibility to pneumococcal colonization by impairing the mucociliary activity of the airway mucosa, reducing the function and production of key antimicrobial peptides, and upregulating an important pneumococcal adherence factor on respiratory epithelial cells. Air pollutant exposure can also impair the phagocytic killing ability of macrophages, permitting increased replication of S. pneumoniae. In addition, particulate matter has been shown to activate various extra- and intracellular receptors of airway epithelial cells, which may lead to increased proinflammatory cytokine production. This increases recruitment of innate immune cells, including macrophages and neutrophils. The inflammatory response that ensues may result in significant tissue damage, thereby increasing susceptibility to invasive disease, because it allows S. pneumoniae access to the underlying tissues and blood. This review provides an in-depth understanding of the interaction between air pollution and the pneumococcus, which has the potential to aid the development of novel treatments or alternative strategies to prevent disease, especially in areas with high concentrations of air pollution.

Recurrent Acute Otitis Media Environmental Risk Factors: A Literature Review from the Microbiota Point of View

Acute otitis media (AOM) constitutes a multifactorial disease, as several host and environmental factors contribute to its occurrence. Prevention of AOM represents one of the most important goals in pediatrics, both in developing countries, in which complications, mortality, and deafness remain possible consequences of the disease, compared to in developed countries, in which this condition has an important burden in terms of medical, social, and economical implications. The strategies for AOM prevention are based on reducing the burden of risk factors, through the application of behavioral, environmental, and therapeutic interventions. The introduction of culture-independent techniques has allowed high-throughput investigation of entire bacterial communities, providing novel insights into the pathogenesis of middle ear diseases through the identification of potential protective bacteria. The upper respiratory tract (URT) is a pivotal region in AOM pathogenesis, as it could act as a source of pathogens than of protective microorganisms for the middle ear (ME). Due to its direct connection with the external ambient, the URT is particularly exposed to the influence of environmental agents. The aim of this review was to evaluate AOM environmental risk factors and their impact on URT microbial communities, and to investigate AOM pathogenesis from the microbiota perspective.

Research on adaption to air pollution in Chinese cities: Evidence from social media-based health sensing

Air pollution seriously threats to human health. Understanding the health effects of air pollution is of great importance for developing countermeasures. However, little is known about the real-time impacts of air pollution on the human heath in a comprehensive way in developing nations, like China. To fill this research gap, the Chinese urbanites' health were sensed from more than 210.82 million Weibo (Chinese Twitter) data in 2017. The association between air pollution and the health sensing were quantified through generalized additive models, based on which the sensitivities and adaptions to air pollution in 70 China's cities were assessed. The results documented that the Weibo data can well sense urbanites' health in real time. With the different geographical characteristics and socio-economic conditions, the Chinese residents have adaption to air pollution, indicated by the spatial heterogeneity of the sensitivities to air pollution. Cities with good air quality in South China and East China were more sensitive to air pollution, while cities with worse air quality in Northwest China and North China were less sensitive. This research provides a new perspective and methodologies for health sensing and the health effect of air pollution.

Nasal Microbiome Change During and After Exacerbation in Asthmatic Children

Airway and gut microbiota are important in asthma pathogenesis. Although several studies have revealed distinct microbiota in asthmatic airways at baseline compared to healthy controls, limited studies compared microbiota during acute exacerbation (AE) and in the recovery phase (RP) in the same asthmatic children. We aim to investigate association between microbiota and asthma status in children and explore their relationship with clinical features of asthma. We recruited 56 asthmatic children and investigated their nasal, throat, and stool microbiota during AE and in the RP. Totally, 320 samples were subjected to 16S rRNA sequencing. Although the microbial communities were clearly separated by body site, within each site the overall communities during AE and in the RP could not be distinguished. Most nasal microbiota were dominated by only one or two of six bacterial genera. The domination was associated with mite allergy and patient age only during AE but not in the RP. When moving into RP, the relative abundance of Staphylococcus increased while that of Moraxella decreased. Throat and stool microbiota were not associated with most of the clinical features. Interestingly, stool microbiota during AE was associated with ABO blood type and stool microbiota in the RP was associated with frequency of the subsequent exacerbations. In summary, the association between nasal microbiota and mite allergy only during AE suggests an altered local immunity and its interplay with nasal microbes. Our work provides a basis for studying microbes, and prevention or therapeutic strategy in childhood asthma, especially during AE.

The Upper Airway Microbiota, Environmental Exposures, Inflammation, and Disease

Along with playing vital roles in pathogen exclusion and immune system priming, the upper airways (UAs) and their microbiota are essential for myriad physiological functions such as conditioning and transferring inhaled air. Dysbiosis, a microbial imbalance, is linked with various diseases and significantly impedes the quality of one’s life. Daily inhaled exposures and/or underlying conditions contribute to adverse changes to the UA microbiota. Such variations in the microbial community exacerbate UA and pulmonary disorders via modulating inflammatory and immune pathways. Hence, exploring the UA microbiota’s role in maintaining homeostasis is imperative. The microbial composition and subsequent relationship with airborne exposures, inflammation, and disease are crucial for strategizing innovating UA diagnostics and therapeutics. The development of a healthy UA microbiota early in life contributes to normal respiratory development and function in the succeeding years. Although different UA cavities present a unique microbial profile, geriatrics have similar microbes across their UAs. This lost community segregation may contribute to inflammation and disease, as it stimulates disadvantageous microbial–microbial and microbial–host interactions. Varying inflammatory profiles are associated with specific microbial compositions, while the same is true for many disease conditions and environmental exposures. A shift in the microbial composition is also detected upon the administration of numerous therapeutics, highlighting other beneficial and adverse side effects. This review examines the role of the UA microbiota in achieving homeostasis, and the impact on the UAs of environmental airborne pollutants, inflammation, and disease.