nitrogen-dioxide and Influenza--Human

This study examined the effects of nitrogen dioxide (NO(2)) exposure on airway inflammation, blood cells, and antiviral respiratory defense. Twenty-one healthy volunteers were exposed on separate occasions to air and 0.6 and 1.5 ppm NO(2) for 3 h with intermittent moderate exercise. Phlebotomy and bronchoscopy were performed 3.5 h after each exposure, and recovered cells were challenged with respiratory viruses in vitro. Blood studies revealed a 4.1% NO(2) dose-related decrease in hematocrit (P = 0.003). Circulating total lymphocytes (P = 0.024) and T lymphocytes (P = 0.049) decreased with NO(2) exposure. Exposure to NO(2) increased the blood lymphocyte CD4(+)-to-CD8(+) ratio from 1.74 +/- 0.11 to 1.85 +/- 0.12 in males but decreased it from 1.88 +/- 0.19 to 1.78 +/- 0.19 in females (P < 0.001 for gender difference). Polymorphonuclear leukocytes in bronchial lavage increased with NO(2) exposure (P = 0.003). Bronchial epithelial cells obtained after exposure to 1.5 ppm NO(2) released 40% more lactate dehydrogenase after challenge with respiratory syncytial virus than with air exposure (P = 0.024). In healthy subjects, exposures to NO(2) at levels found indoors cause mild airway inflammation, effects on blood cells, and increased susceptibility of airway epithelial cells to injury from respiratory viruses.

Topics: Adult; Air; Blood Cells; Bronchi; Bronchoalveolar Lavage Fluid; CD4-CD8 Ratio; Cell Survival; Disease Susceptibility; Dose-Response Relationship, Drug; Double-Blind Method; Epithelial Cells; Female; Humans; Influenza, Human; L-Lactate Dehydrogenase; Lymphocytes; Male; Neutrophils; Nitrogen Dioxide; Phenotype; Respiratory Syncytial Virus Infections

The effect of NO2 exposure and human susceptibility to respiratory virus infection was investigated in a placebo-controlled, randomized, double-blind trial conducted in an environmentally controlled research chamber over 3 yr. Healthy, nonsmoking, young adult volunteers who were seronegative to influenza A/Korea/82 (H3N2) virus were randomly assigned to breathe either filtered clean air (control group) or NO2 for 2 h/day for 3 consecutive days. The NO2 concentrations were 2 ppm (Year 1), 3 ppm (Year 2), and 1 or 2 ppm (Year 3). Live, attenuated cold-adapted (ca) influenza A/Korea/82 reassortant virus was administered intranasally to all subjects immediately after the second exposure. Only one of the 152 volunteers had any symptoms; this person had a low grade fever. Pulmonary function measurements and nonspecific airway reactivity to methacholine were unchanged after NO2 exposure, virus infection, or both. Infection was determined by virus recovery, a fourfold or greater increase in serum or nasal wash influenza-specific antibody titers, or both. The infection rates of the groups were 12/21 (2 ppm NO2) versus 15/23 (clean air) in Year 1, 17/22 (3 ppm NO2) versus 15/21 (clean air) in Year 2, and 20/22 (2 ppm) and 20/22 (1 ppm) versus 15/21 (clean air) in Year 3. Each group exposed to 1 or 2 ppm NO2 in the last year became infected more often (91%) than did the control group (71%), but the differences were not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adolescent; Adult; Air Pollutants; Atmosphere Exposure Chambers; Disease Susceptibility; Dose-Response Relationship, Drug; Double-Blind Method; Humans; Influenza A virus; Influenza, Human; Nitrogen Dioxide; Random Allocation; Respiratory Function Tests; Time Factors

The interaction between nitrogen dioxide (NO2) exposure and human susceptibility to respiratory virus infection was investigated in a placebo-controlled, randomized, blinded trial that was conducted in an environmentally controlled research chamber over a three-year period. Healthy, non-smoking volunteers, 18 to 35 years old, who were seronegative to influenza A/Korea/82 (H3N2) virus, were randomly assigned either to breathe filtered clean air (clean air group) or nitrogen dioxide (exposure group) for two hours a day for three consecutive days. The nitrogen dioxide concentrations were 2 ppm (Year 1), 3 ppm (Year 2), and 1 or 2 ppm (Year 3). Live, attenuated cold-adapted (ca) influenza A/Korea/82 reassortant virus was administered intranasally to all subjects after the second day of exposure. Only one of the 152 volunteers had any symptoms, and that subject had only a low-grade fever. No adverse changes in pulmonary function or nonspecific airway reactivity to methacholine were observed after 2 or 3 ppm nitrogen dioxide exposure, virus infection, or both. Infection was defined by virus recovery, a four-fold or greater increase in serum or nasal wash influenza-specific antibody titers, or both. The infection rates of the groups exposed to nitrogen dioxide and those breathing clean air were: 12/21 (2 ppm nitrogen dioxide) versus 15/23 (clean air) in Year 1; 17/22 (3 ppm nitrogen dioxide) versus 15/21 (clean air) in Year 2; and 20/22 (2 ppm nitrogen dioxide) and 20/22 (1 ppm nitrogen dioxide) versus 15/21 (clean air) in Year 3. Although the differences were not statistically significant, the groups exposed to 1 or 2 ppm nitrogen dioxide in the last year became infected more often (91 percent) than those breathing clean air (71 percent). The frequencies of infection in two of the four groups exposed to nitrogen dioxide were higher than the 56 to 73 percent infection rate observed in previous studies in healthy human volunteers with the same dose of ca-influenza A (H3N2) virus. Our findings suggest, but do not prove, that nitrogen dioxide alone may play a role in increasing the susceptibility of adults to respiratory virus infections.

Topics: Adolescent; Adult; Disease Susceptibility; Dose-Response Relationship, Drug; Double-Blind Method; Humans; Influenza, Human; Lung Volume Measurements; Nitrogen Dioxide; Randomized Controlled Trials as Topic

Influenza is an important cause of paediatric illness across the globe. However, information about the relationships between air pollution, meteorological variability and paediatric influenza A and B infections in tropical settings is limited.. We analysed all daily reports of influenza A and B infections in children <5 years old obtained from the largest specialist women and children's hospital in Singapore. In separate negative binomial regression models, we assessed the dependence of paediatric influenza A and B infections on air quality and meteorological variability, using multivariable fractional polynomial modelling and adjusting for time-varying confounders.. Approximately 80% of 7329 laboratory-confirmed reports were caused by influenza A. We observed positive associations between sulphur dioxide (SO. We observed different independent associations between air quality and meteorological variability with paediatric influenza A and B infections. Anticipated seasonal infection peaks and variations in air quality and meteorological parameters can inform the timing of community measures aimed at reducing influenza infection risk.

Topics: Air Pollutants; Air Pollution; Child; Child, Preschool; Female; Herpesviridae Infections; Humans; Influenza, Human; Nitrogen Dioxide; Singapore

The impact of exposure to ambient pollutants on influenza transmissibility is poorly understood. We aim to examine the associations of six ambient pollutants with influenza transmissibility in China and assess the effect of the depletion of susceptibles.. Provincial-level surveillance data on weekly influenza-like illness (ILI) incidence and viral activity were utilized to estimate the instantaneous reproduction number (R. There is a significantly positive correlation between influenza transmissibility and five distinct ambient pollutants: PM. Most ambient pollutants may potentially contribute to the facilitation of human-to-human influenza virus transmission in China. This observed association was maintained even after adjusting for variation in the susceptible population.

Topics: Air Pollutants; Air Pollution; China; Environmental Pollutants; Humans; Influenza, Human; Nitrogen Dioxide; Particulate Matter

Currently, the influenza epidemic in China is at a high level and mixed with other respiratory diseases. Current studies focus on regional influenza and the impact of environmental pollutants on time series, and lack of overall studies on the national influenza epidemic and the nonlinear correlation between environmental pollutants and influenza. The unclear spatial and temporal evolution patterns of influenza as well as the unclear correlation effect between environmental pollutants and influenza epidemic have greatly hindered the prevention and treatment of influenza epidemic by relevant departments, resulting in unnecessary economic and human losses.. This study used Chinese influenza incidence data for 2007-2017 released by the China CDC and air pollutant site monitoring data. Seasonal as well as inter monthly differences in influenza incidence across 31 provinces of China have been clarified through time series. Space-Time Cube model (STC) was used to investigate the spatio-temporal evolution of influenza incidence in 315 Chinese cities during 2007-2017. Then, based on the spatial heterogeneity of influenza incidence in China, Generalized additive model (GAM) was used to identify the correlation effect of environmental pollutants (PM. The influenza incidence in China had obvious seasonal changes, with frequent outbreaks in winter and spring. The influenza incidence decreased significantly after March, with only sporadic outbreaks occurring in some areas. In the past 11 years, the influenza epidemic had gradually worsened, and the clustering of influenza had gradually expanded, which had become a serious public health problem. The correlation between environmental pollutants and influenza incidence was nonlinear. Generally, PM. The study found that the influenza epidemic in China was in a rapidly rising stage, and several regions had a multi-year outbreak trend and the hot spots continue to expand outward. The association between environmental pollutants and influenza incidence was nonlinear and spatially heterogeneous. Relevant departments should improve the monitoring of influenza epidemic, optimize the allocation of resources, reduce environmental pollution, and strengthen vaccination to effectively prevent the aggravation and spread of influenza epidemic in the high incidence season and areas.

Topics: China; Environmental Pollutants; Humans; Incidence; Influenza, Human; Nitrogen Dioxide; Particulate Matter

Influenza is a serious public health problem, and its prevalence and spread show significant spatiotemporal characteristics. Previous studies have found that air pollutants are linked to an increased risk of influenza. However, the mechanism of influence and the degree of their association have not been determined. This study aimed to determine the influence of the air environment on the spatiotemporal distribution of influenza.. The kernel density estimation and Getis-Ord. The results of the sensitivity analysis using Spearman's correlation coefficients showed the following ranking of the contributions of the air pollutants to the influenza incidence in descending order: SO. The influenza incidence showed a strong spatial correlation and associated sensitivity to changes in concentrations of air pollutants. Hypersensitive areas were mainly located in the southeastern part of northeastern China, the coastal areas of the Yellow River Basin, the Beijing-Tianjin-Hebei region and surrounding areas, and the Yangtze River Delta. The influenza incidence was most sensitive to CO, NO

Topics: Air Pollutants; Air Pollution; China; Cities; Humans; Incidence; Influenza, Human; Nitrogen Dioxide; Particulate Matter

Evidence suggests that air pollution is associated with many adverse health outcomes such as cardiovascular diseases (CVD), respiratory diseases, cancer, and birth defects. Yet few studies dig into the relationship between air pollution and airborne infectious diseases.. Daily data on influenza incidence were obtained from Hubei Provincial Center for Disease Control and Prevention (Hubei CDC). Data on air pollutants including nitrogen dioxide (NO. In the single-day lag model, the largest effect estimates were observed at lag 0. An increased relative risk (RR) of influenza was significantly associated with a 10 μg/m. Our study shows that air pollution may be associated with the risk of influenza in a broad sense. Therefore, when formulating policies to deal with influenza outbreaks in the future, factors regarding air pollution should be taken into consideration.

Topics: Air Pollutants; Air Pollution; China; Humans; Incidence; Influenza, Human; Nitrogen Dioxide; Particulate Matter

Little information exists on interaction effects between air pollution and influenza vaccination on allergic respiratory diseases. We conducted a large population-based study to evaluate the interaction effects between influenza vaccination and long-term exposure to ambient air pollution on allergic respiratory diseases in children and adolescents.. A cross-sectional study was investigated during 2012-2013 in 94 schools from Seven Northeastern Cities (SNEC) in China. Questionnaires surveys were obtained from 56 137 children and adolescents aged 2-17 years. Influenza vaccination was defined as receipt of the influenza vaccine. We estimated air pollutants exposure [nitrogen dioxide (NO. We found statistically significant interactions between influenza vaccination and air pollutants on allergic respiratory diseases and related symptoms (doctor-diagnosed asthma, current wheeze, wheeze, persistent phlegm and allergic rhinitis). The adjusted ORs for doctor-diagnosed asthma, current wheeze and allergic rhinitis among the unvaccinated group per interquartile range (IQR) increase in PM. Influenza vaccination may play an important role in mitigating the detrimental effects of long-term exposure to ambient air pollution on childhood allergic respiratory diseases. Policy targeted at increasing influenza vaccination may yield co-benefits in terms of reduced allergic respiratory diseases.

Topics: Adolescent; Air Pollutants; Air Pollution; Asthma; Child; Child, Preschool; China; Cities; Cross-Sectional Studies; Environmental Exposure; Female; Humans; Hypersensitivity; Influenza, Human; Logistic Models; Male; Nitrogen Dioxide; Particulate Matter; Respiration Disorders; Respiratory Sounds; Respiratory Tract Diseases; Risk Factors; Schools; Surveys and Questionnaires; Vaccination

Ambient air pollution exposure and influenza virus infection have been documented to be independently associated with reduced lung function previously. Influenza vaccination plays an important role in protecting against influenza-induced severe diseases. However, no study to date has focused on whether influenza vaccination may modify the associations between ambient air pollution exposure and lung function.. We undertook a cross-sectional study of 6740 children aged 7-14 years into Seven Northeast Cities (SNEC) Study in China during 2012-2013. We collected information from parents/guardians about sociodemographic factors and influenza vaccination status in the past three years. Lung function was measured using portable electronic spirometers. Machine learning methods were used to predict 4-year average ambient air pollutant exposures to nitrogen dioxide (NO. Ambient air pollution were observed significantly associated with reductions in lung function among children. We found significant interactions between influenza vaccination and air pollutants on lung function, suggesting greater vulnerability to air pollution among unvaccinated children. For example, an interaction (p. Our results suggest that influenza vaccination may moderate the detrimental effects of ambient air pollution on lung function among children. This study provides new insights into the possible co-benefits of strengthening and promoting global influenza vaccination programs among children.

Topics: Adolescent; Air Pollutants; Air Pollution; Child; China; Cities; Cross-Sectional Studies; Environmental Exposure; Female; Humans; Influenza, Human; Male; Nitrogen Dioxide; Particulate Matter; Vaccination

Accumulating evidence suggests that air pollution is a risk factor for adverse respiratory and cardiovascular health outcomes. However, the different impacts of exposure to air pollutants on influenza virus activity and influenza-like illness (ILI) have not been well documented in epidemiological studies. We examined the association between air pollutants of particular matters < 2.5 μm (PM

Topics: Air Pollutants; China; Cities; Clinical Laboratory Techniques; Environmental Exposure; Humans; Incidence; Influenza, Human; Nitrogen Dioxide; Particulate Matter; Sulfur Dioxide

Influenza-like illness causes substantial morbidity and mortality. Air pollution has already been linked to many health issues, and increasing evidence in recent years supports an association between air pollution and respiratory infections. It is a pioneer study in China to quantify the effects of air pollution on influenza-like illness. This study used wavelet coherence analysis and generalized additive models to explore the potential association between air pollution (including particulate matter with aerodynamic diameter ≦2.5 μm (PM2.5), particulate matter with aerodynamic diameter ≦10 μm (PM10) and nitrogen dioxide (NO2)) and influenza-like illness (a total of 59860 cases) in Nanjing, China from January 1, 2013 to December 31, 2013. The average concentrations of PM2.5, PM10 and NO2 were 77.37 μg/m(3), 135.20 μg/m(3) and 55.80 μg/m(3). An interquartile range increase in PM2.5 concentration was associated with a 2.99% (95% confidence interval (CI): 1.64%, 4.36%) increase in daily influenza-like cases on the same day, while the corresponding increase in NO2 was associated with a 3.77% (95% CI: 2.01%, 5.56%) increase in daily cases. People aged 0-4 were proved to be significantly susceptible to PM10 and NO2; 5-14 ages were significantly susceptible to PM2.5 and PM10; and 15-24 ages were significantly susceptible to all the analyzed air pollutants. Air pollution effects tended to be null or negative for patients aged over 25, which might be due to the small number of influenza-like cases in this age group. This study can be useful for understanding the adverse health effects of air pollution and the cause of influenza-like illness.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Air Pollutants; Child; Child, Preschool; China; Cities; Environmental Exposure; Humans; Infant; Infant, Newborn; Influenza, Human; Middle Aged; Models, Theoretical; Nitrogen Dioxide; Particle Size; Particulate Matter; Respiratory Tract Infections; Young Adult

Chronic obstructive pulmonary disease (COPD) is a prevalent condition in adults aged ≥40 years characterized by progressive airflow limitation associated with chronic inflammatory response to noxious particles in the airways and lungs. Smoking, genetics, air pollution, nutrition and other factors may influence COPD development. Most hospitalizations and deaths for COPD are caused by its acute exacerbations, which greatly affect the health and quality of life of COPD patients and pose a high burden on health services. The aims of this project were to identify trends, geographic patterns and risk factors for COPD exacerbations, as revealed by hospitalizations and deaths, in the Basque Country, Spain, over a period of 12 years (2000-2011). Hospitalization and mortality rates for COPD were 262 and 18 per 100,000 population, respectively, with clusters around the biggest cities. Hospital mortality was 7.4%. Most hospitalized patients were male (77.4%) and accounted for 72.1% of hospital mortality. Hospitalizations decreased during the study period, except for 50-64 year-old women, peaking significantly. Using a multivariate modeling approach it was shown that hospitalizations were positively correlated with increased atmospheric concentrations of NO

Topics: Age Factors; Aged; Aged, 80 and over; Air Pollutants; Carbon Monoxide; Cities; Disease Progression; Environmental Exposure; Female; Hospital Mortality; Hospitalization; Humans; Influenza, Human; Male; Middle Aged; Nitrogen Dioxide; Ozone; Particulate Matter; Pulmonary Disease, Chronic Obstructive; Risk Factors; Sex Factors; Smoking; Spain; Sulfur Dioxide; Temperature

Exacerbations of chronic obstructive pulmonary disease (COPD) contribute greatly to increased morbidity, mortality and diminished quality of life. Recent studies report moderately strong positive associations between exposures to several air pollutants and COPD-related emergency department (ED) visits and hospital admissions (HA). Studies that use clinically defined exacerbations rather than counting ED visits and HA may be more sensitive to environmental triggers like air pollution, but very few such studies exist. Participants in a COPD disease management group living in an area of low air pollution and who were followed closely for the earliest signs of an exacerbation provided an opportunity to study associations between air pollution and COPD exacerbation.. Associations between short term exposures to air pollutants, including sulfur dioxide (SO. We found that short-term exposures to SO. Despite living in an area with air pollution concentrations below current USEPA NAAQS, these COPD patients appeared to suffer increased risk of COPD exacerbation following short-term exposures to increased concentrations of SO

Topics: Aged; Air Pollutants; Air Pollution; Environmental Monitoring; Female; Humans; Humidity; Influenza, Human; Male; Massachusetts; Middle Aged; Nitrogen Dioxide; Odds Ratio; Particulate Matter; Pulmonary Disease, Chronic Obstructive; Sulfur Dioxide; Temperature

Previous studies have demonstrated the importance of weather variables in influencing the incidence of influenza. However, the role of air pollution is often ignored in identifying the environmental drivers of influenza. This research aims to examine the impacts of air pollutants and temperature on the incidence of pediatric influenza in Brisbane, Australia. Lab-confirmed daily data on influenza counts among children aged 0-14years in Brisbane from 2001 January 1st to 2008 December 31st were retrieved from Queensland Health. Daily data on maximum and minimum temperatures for the same period were supplied by the Australian Bureau of Meteorology. Winter was chosen as the main study season due to it having the highest pediatric influenza incidence. Four Poisson log-linear regression models, with daily pediatric seasonal influenza counts as the outcome, were used to examine the impacts of air pollutants (i.e., ozone (O3), particulate matter≤10μm (PM10) and nitrogen dioxide (NO2)) and temperature (using a moving average of ten days for these variables) on pediatric influenza. The results show that mean temperature (Relative risk (RR): 0.86; 95% Confidence Interval (CI): 0.82-0.89) was negatively associated with pediatric seasonal influenza in Brisbane, and high concentrations of O3 (RR: 1.28; 95% CI: 1.25-1.31) and PM10 (RR: 1.11; 95% CI: 1.10-1.13) were associated with more pediatric influenza cases. There was a significant interaction effect (RR: 0.94; 95% CI: 0.93-0.95) between PM10 and mean temperature on pediatric influenza. Adding the interaction term between mean temperature and PM10 substantially improved the model fit. This study provides evidence that PM10 needs to be taken into account when evaluating the temperature-influenza relationship. O3 was also an important predictor, independent of temperature.

Topics: Adolescent; Air Pollutants; Air Pollution; Child; Child, Preschool; Female; Humans; Infant; Infant, Newborn; Influenza, Human; Linear Models; Male; Models, Theoretical; Nitrogen Dioxide; Ozone; Particulate Matter; Queensland; Seasons; Temperature; Time Factors; Weather

Populations in Asia are not only at risk of harm to their health through environmental degradation as a result of worsening pollution problems but also constantly threatened by recurring and emerging influenza epidemics and. pandemics. Situated in the area with the world's fastest growing economy and close to hypothetical epicenters of influenza transmission, Hong Kong offers a special opportunity for testing environmental management and public health surveillance in the region. In the Public Health and Air Pollution in Asia (PAPA*) project, the Hong Kong research team assessed the health effects of air pollution and influenza as well as the interaction between them. The team also assessed disparities in the health effects of air pollution between relatively deprived and more affluent areas in Hong Kong. The aim was to provide answers to outstanding research questions relating to the short-term effects of air pollution on mortality and hospital admissions; the health effects of influenza with a view to validating different measures of influenza activity according to virologic data; the confounding effects of influenza on estimates of the health effects of air pollution; the modifying effects of influenza on the health effects of air pollution; and the modifying effects of neighborhood social deprivation on the health effects of air pollution.. Data on mortality and hospital admissions for all natural causes, as well as the subcategories of cardiovascular diseases (CVD) and respiratory diseases (RD), were derived from the Hong Kong Census and Statistics Department and the Hospital Authority. Daily concentrations of nitrogen dioxide (NO2), sulfur dioxide (SO2), particulate matter with an aerodynamic diameter < or = 10 pm (PM10); and ozone (O3) were derived from eight monitoring stations with hourly data that were at least 75% complete during the study period. Three measures of influenza and respiratory syncytial virus (RSV) activity were derived from positive isolates of specimens in the virology laboratory of Queen Mary Hospital (QMH), the main clinical teaching center at The University of Hong Kong and part of the Hong Kong Hospital Authority network of teaching hospitals: influenza intensity (defined as the weekly proportion of positive isolates of influenza in the total number of specimens received for diagnostic tests); the presence of influenza epidemic (defined as a period when the weekly frequency of these positive isolates is > or = 4% of the annual total number of positive isolates [i.e., twice the expected mean value] in two or more consecutive weeks); and influenza predominance (defined as a period of influenza epidemic when the weekly frequency of RSV was less than 2% for two or more consecutive weeks). The weekly proportion of positive isolates of RSV in total specimens was determined in the same way as for influenza intensity. A social deprivation index (SDI) was defined by taking the average of the proportions of households or persons with the following six characteristics in each geographic area using the census statistics: unemployment; household income < U.S. $250 per month; no schooling at all; never-married status; one-person household; and subtenancy. A Poisson regression with quasi-likelihood to account for overdispersion was used to develop core models for daily health outcomes, with a natural spline smoothing function to filter out seasonal patterns and long-term trends in this time-series study of daily mortality and hospital admissions, and with adjustment for days of the week, temperature, and relative humidity (RH). Air pollutant concentration values were entered into the core model to assess the health effects of specific pollutants. The possible confounding effects of influenza were assessed by observing changes in magnitude of the effect estimate when each influenz

Topics: Adolescent; Adult; Age Factors; Aged; Air Pollutants; Air Pollution; Child; Child, Preschool; Female; Hong Kong; Humans; Infant; Infant, Newborn; Influenza, Human; Male; Middle Aged; Nitrogen Dioxide; Ozone; Particulate Matter; Patient Admission; Respiratory Syncytial Virus Infections; Respiratory Tract Infections; Seasons; Sex Factors; Sulfur Dioxide; Time Factors; Young Adult

Topics: Air Pollutants; Humans; Influenza, Human; Nitrogen Dioxide; Research; Respiratory Tract Infections; Risk Factors

Topics: Air Pollution; Child; Disease Outbreaks; Environmental Exposure; Female; Humans; Influenza, Human; Male; Mass Screening; Nitrogen Dioxide; Respiratory Tract Diseases; Respiratory Tract Infections; Tennessee