Improving air quality starts at home

Identifies household air pollution (HAP) as a major health risk, especially in poor countries which rely on biomass for cooking. Particulate matter concentration in indoor kitchens that use solid fuels for cooking account for an estimated 370,000 premature deaths globally based on 2014 data. Direct health impacts include chronic obstructive pulmonary disease, lung disease, and cataracts while children face acute lower respiratory infections. Interventions offer cleaner stoves through national stove programs and the development of standards and guidelines to promote only the cleanest devices, emphasizing the optimal use of electricity, natural gas, or LPG. Little benefit comes from converting individual users, so interventions need to target communities to become “smokeless” villages. Successful stove programs typically involve a public subsidy for the poor and because of savings on health care costs, its expense can be justified. Full adoption of a newer technology for clean cooking may not occur until generational change, with the present generation continuing to use the traditional methods despite the benefits to the family of the cleaner technology.

Acute respiratory tract infections are the leading cause of emergency department visits and hospitalizations in US children, with highest risks in the first 2 months after birth. Out-of-home childcare settings increase the spread of respiratory tract infections. The study team hypothesized that access to state-paid family leave could reduce acute care encounters (hospital admissions or emergency department visits) for respiratory tract infections in young infants by reducing out-of-home childcare transmissions. To determine if the 2018 introduction of paid family leave in New York state reduced acute care encounters for respiratory tract infections in infants 8 weeks or younger. This population-based study of acute care encounters took place in New York state and New England control states (Maine, Massachusetts, New Hampshire, Vermont) from October 2015 through February 2020. Participants included infants aged 8 weeks or younger. Controlled time series analysis using Poisson regression was used to estimate the impact of paid family leave on acute care encounters for respiratory tract infections, comparing observed counts during respiratory virus season (October through March) with those predicted in the absence of the policy. Acute care encounters for respiratory tract infections in 1-year-olds (who would not be expected to benefit as directly from the policy) were modeled as a placebo test. New York State Paid Family Leave policy, introduced on January 1, 2018, providing 8 weeks of paid leave for eligible parents. Emergency department visits or hospitalizations with International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD) codes for upper or lower respiratory tract infections or associated symptoms (ie, fever, cough), excluding newborn hospitalizations. The secondary outcome was acute care encounters for respiratory syncytial virus (RSV) bronchiolitis. There were 52 943 acute care encounters for respiratory infection among infants 8 weeks or younger. There were 15 932 encounters that were hospitalizations (30%) and 33 304 of the encounters were paid for by Medicaid (63%). Encounters were 18% lower than predicted (relative percentage change = -17.9; 95% CI, -20.3 to -15.7) after the introduction of paid family leave. RSV encounters were 27.0% lower (95% CI, -30.9 to -23.5) than predicted. Similar reductions were not observed in 1-year-olds (relative percentage change = -1.5; 95% CI, -2.5 to -0.6). New York state's paid family leave policy was associated with reduced acute care encounters for respiratory tract infections in young infants. These findings may be useful for informing implementation of paid family leave federally and in the states that have not enacted paid family leave policies.

In Memoriam: Kirk R. Smith.

Background: High levels of household air pollution (HAP) occur in houses of many developing countries due to combustion of biomass fuels (wood, charcoal, cow dung, crop residues) in the households in open fires or inefficient stoves. Particulate Matter (PM2.5) and Volatile Organic Compounds (VOCs) are among the significant pollutants that are generated and can adversely affect the health of the exposed. Therefore, we monitored PM2.5 and VOC in selected rural and urban areas of the Copperbelt province of Zambia in order to measure the magnitude and correlates of HAP concentration levels. Methods: Indoor PM2.5 particles Results: Biomass fuel use in our study area was the dominant source of household energy for cooking. Mean indoor PM 2.5 varied greatly between households depending on fuel and kitchen type while the variations in VOC were not that much. Concentration levels for PM2.5 varied between 79 µg/m3 and 921 µg/m3, with an overall mean (SD) for daily average of 444.5 µg/m3 (170.2) while for VOC concentration levels ranged from 245 ppb to 393 ppb with an overall mean (SD) for daily average of 342 ppb (25.3). The median (Q1, Q2) indoor PM2.5 during cooking time was 501(411,686) µg/m3 and daily average 393(303,578) µg/m3 while VOC daily average was 343(320, 363) ppb concentrations in the entire study population. Conclusion: Household air pollution mean concentrations in rural and urban settings of Ndola and Masaiti excessively exceed the WHO guidelines; hence continued efforts through research and advocacy are needed to mitigate the health damaging levels of household air pollution.

Letter from India.

BackgroundRespiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infection in infants, and a need exists for prevention of RSV in healthy infants. Nirsevimab is a monoclonal antibody with an extended half-life that is being developed to protect infants for an entire RSV season with a single intramuscular dose.MethodsIn this trial conducted in both northern and southern hemispheres, we evaluated nirsevimab for the prevention of RSV-associated lower respiratory tract infection in healthy infants who had been born preterm (29 weeks 0 days to 34 weeks 6 days of gestation). We randomly assigned the infants in a 2:1 ratio to receive nirsevimab, at a dose of 50 mg in a single intramuscular injection, or placebo at the start of an RSV season. The primary end point was medically attended RSV-associated lower respiratory tract infection through 150 days after administration of the dose. The secondary efficacy end point was hospitalization for RSV-associated lower respiratory tract infection through 150 days after administration of the dose.ResultsFrom November 2016 through November 2017, a total of 1453 infants were randomly assigned to receive nirsevimab (969 infants) or placebo (484 infants) at the start of the RSV season. The incidence of medically attended RSV-associated lower respiratory tract infection was 70.1% lower (95% confidence interval [CI], 52.3 to 81.2) with nirsevimab prophylaxis than with placebo (2.6% [25 infants] vs. 9.5% [46 infants]; P<0.001) and the incidence of hospitalization for RSV-associated lower respiratory tract infection was 78.4% lower (95% CI, 51.9 to 90.3) with nirsevimab than with placebo (0.8% [8 infants] vs. 4.1% [20 infants]; P<0.001). These differences were consistent throughout the 150-day period after the dose was administered and across geographic locations and RSV subtypes. Adverse events were similar in the two trial groups, with no notable hypersensitivity reactions.ConclusionsA single injection of nirsevimab resulted in fewer medically attended RSV-associated lower respiratory tract infections and hospitalizations than placebo throughout the RSV season in healthy preterm infants. (Funded by AstraZeneca and Sanofi Pasteur; ClinicalTrials.gov number, NCT02878330.)

This paper attempts to analyse the nature of relationship between the levels of Household Air Pollution (HAP) and incidence of morbidity in urban India along with the pattern of its regional variations. It also explores the causal connection between the incidence of air-related diseases and HAP, giving control for outdoor pollution. Whether these effects are sensitive to the overall level of economic development is an issue of our interest. Therefore, the States/UTs of India are grouped, in terms of different developmental parameters, using Multidimensional Scaling and Clustering technique, and the relation between HAP and morbidity has been analysed for each group of states by applying stepwise regression techniques. The study of this heterogeneity helped us provide more focused policy prescriptions. Different policy prescriptions in terms of education as well as exposure to HAP and fuel choices have been suggested for different clusters.

Half of the world's population still relies on solid fuels to fulfill its energy needs for cooking and space heating, leading to high levels of household air pollution (HAP), adversely affecting human health and the environment. A cross-sectional cohort study was conducted to investigate any associations between: (1) HAP metrics (mass concentration of particulate matter of aerodynamic size less than 2.5μm (PM2.5 ), lung-deposited surface area (LDSA) and carbon monoxide (CO)); (2) a range of household and socio-demographic characteristics; and (3) lung function for women and children exposed daily to biomass cookstove emissions, in rural southern India. HAP measurements were collected inside the kitchen of 96 households, and pulmonary function tests were performed for the women and child in each enrolled household. Detailed questionnaires captured household characteristics, health histories and various socio-demographic parameters. Simple linear and logistic regression analysis was performed to examine possible associations between the HAP metrics, lung function and all household/socio-demographic variables. Obstructive lung defects (forced vital capacity (FVC)≥lower limit of normal (LLN) and forced expiratory volume in 1second (FEV1 )/FVC<LLN) were found in 8% of mothers and 9% of children, and restrictive defects (FVC<LLN and FEV1 /FVC≥LLN) were found in 17% of mothers and 15% of children. A positive association between LDSA, included for the first time in this type of epidemiological study, and lung function was observed, indicating LDSA is a superior metric compared to PM2.5 to assess effects of PM on lung function. HAP demonstrated a moderate association with subnormal lung function in children. The results emphasize the need to look beyond mass-based PM metrics to assess fully the association between HAP and lung function.

Pneumonia is one of the leading causes of death in children <5 years, accounting for 1 million of the 5.9 million children <5 who died in 2015, of which more than 98% occurred in low-resource countries. Pneumococcal pneumonia, caused by the bacteria Streptococcus pneumoniae (pneumococcus), is responsible for 30-50% of pneumonia related deaths [3] . Pneumococcal carriage is a precondition for developing pneumococcal pneumonia. Ten of the most common serotypes are estimated to account for 62% of invasive disease worldwide. Exposure to household air pollution (HAP) from solid fuels has been shown to be a risk factor for developing pneumonia. In 2012, over 4 million people died prematurely from illnesses attributed to HAP exposure from cooking with solid fuels, estimated to contribute 2.7% to the global burden of disease and 36% to contributing risk factors for acute respiratory infections globally. In Africa, 94% of rural populations and 73% of urban populations use solid fuels as their primary source of energy. To better understand the relationship between pneumococcal carriage and HAP, including possible interventions to reduce HAP in cookhouses, an intervention study using biomass briquettes and alternative biomass cookstoves was conducted in rural Gambia among women and young children. HAP levels were measured and nasopharyngeal swabs samples were collected to measure the effect that potential reduced HAP pollutant levels had on pneumococcal carriage. This study also assessed the cost of the intervention and whether participants would likely use such an intervention in lieu of the 3-stone stove and wood. No difference in HAP levels between the two cooking methods was found in this study, nor a difference in pneumococcal carriage. Further research needs to be conducted to explore cleaner, more efficient, and less costly methods of cooking in low- and middle-income nations.

BackgroundRespiratory syncytial virus (RSV) causes lower respiratory tract infections (LRTIs) in infants, leading to substantial morbidity and mortality. Nirsevimab, a long-lasting monoclonal antibody, has been demonstrated to reduce RSV-related outcomes in randomized controlled trials (RCTs) and real-world settings. The object was to review the existing real-world evidence (RWE) on the effectiveness of nirsevimab in preventing RSV-LRTIs.MethodsSearches of six databases in addition to trial registries, HTA/regulatory agency webpages and conference abstracts were conducted in November 2024. Observational studies evaluating nirsevimab prophylaxis in infants during their first RSV season or high-risk infants in their second season were included. For outcomes evaluated by more than one study, feasibility assessment was conducted and, where appropriate, studies were combined in meta-analyses.ResultsSixteen studies reporting effectiveness outcomes were included. The studies were conducted across four countries (Spain, Italy, US and France), and included 141,550 infants. Nirsevimab showed significant effectiveness for preventing RSV-LRTI hospitalization (reduction in risk from hazard ratios and odds ratios of 84.5%; 95% CI: 73.6%−90.9%; I2: 0 and 73.7%; 95% CI: 42.3%−88.0%; I2: 0%, respectively), intensive care unit (ICU) admission (85.9%; 95% CI: 13.2%−97.7%) and ventilatory support (87.1%; 95% CI: 70.2%−94.4%). Nirsevimab was also effective in preventing RSV-LRTI visits in primary care (75.8%; 95% CI: 40.4%−92.7%) and emergency departments (87.9%; 70.3%−95.1%).ConclusionsReal-world evidence confirms the effectiveness of nirsevimab against RSV-LRTIs and underlines the public health impact of the intervention in preventing RSV-related health outcomes. There is no clear evidence that effectiveness differs for infants born in season (at birth immunization) compared with out of season groups, or that effectiveness varies in preterm infants compared to healthy term infants.Systematic review registrationhttps://www.crd.york.ac.uk/PROSPERO/view/CRD42024591323.

ASIA is a continent with many people who still have and use biomass or solid fuel use (SFU) for cooking and various household air pollution. Previous research has mentioned the negative effects of household air pollution on the incidence of acute respiratory infections in children under 5 years. Acute respiratory diseases have even become the cause of at least 4 million deaths of children under 5 years old every year in the world. The meta-analysis aimed to estimate the correlation between household air pollution and the incidence of acute respiratory infections in children under five in ASIA. This study was a meta-analysis. Primary data is taken through the electronic databases such as: PubMed, Science Direct, Web of Science, Springer Link and Cochrane Database. By using the search keywords "Household air pollution AND acute respiratory tract infections AND adjusted odds ratio", "indoor air pollution AND acute respiratory tract infections AND adjusted odds ratio", and "paparan asap rumah tangga DAN ISPA DAN adjusted odds ratio". Articles taken between 2013-2023. Statistical analysis was performed using the RevMan 5.3. 7 articles qualified for quantitatively analysis. The exposure of household air pollution can increases the risk of acute respiratory infections 3 times in children under five and statistically significant (OR 3.36; 95% CI: 2.96 – 3.81; p value &lt; 0.001). Exposureto household air pollution is a significant risk factor for the incidence of acute respiratory infections in children under 5 years.&#x0D;

Effect of infant formula supplemented with prebiotics and probiotics on incidence of respiratory tract infections: A systematic review and meta-analysis of randomized clinical trials

The Global Household Air Pollution (HAP) Measurements database, commissioned by the World Health Organization, provides an organized summary of data reported in the literature describing HAP microenvironments, methods and measurements. As of June 2018, the database contains measurements from 43 countries obtained from 196 studies published through 2016. The database includes information useful for understanding the range of household and personal air pollution measurements that have been collected in a country, as well as characteristics of the cooking environment, including primary cooking fuel type, stove type, heating fuel type and kitchen location. Quantitative particulate matter (PM) of various size fractions and/or carbon monoxide (CO) exposure measurements included in the database can be aggregated and analyzed to generate summary statistics (e.g. average sub-national, national, regional and global HAP exposures) to assess temporal and spatial relationships. The quantitative PM exposure measurements in the database have been used in global predictive modeling of HAP-PM2.5 exposures (“Global Estimation of Exposure to Fine Particulate Matter (PM2.5) from Household Air Pollution” (Shupler et al., 2018) [1])

Background:Household and ambient air pollution are jointly responsible for about 7 million premature deaths annually. Women living in slums, with unhealthy environment, both indoors and outdoors, particularly those living close to industrial and/or vehicular pollution zones due to multiple sources of air pollution, are at the higher risk of having impaired lung function tests.Objective:The aim of this study was to estimate the prevalence of abnormal lung functions and to identify the environmental risk factors associated with them among adult women of 18–59 years.Materials and Methods:A total of 550 women aged 18–59 years were approached in a representative urban slum. Five hundred consented to participate and 299 had prebronchodilator spirometry satisfying ATS standards. House visits to assess environmental conditions were conducted to determine their association with forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC). Chi-square test was used to test the association of risk factors with lung functions. ANOVA was used to test the association of mean values of FEV1 and FVC with age.Results:Out of 299 participants with acceptable spirometric curves, 5% had reduced FEV1/FVC ratio than the normal and 26.8% and 17.4% had lower values than predicted for FVC and FEV1, respectively. Altered lung function was related to age, tobacco smoking, and history of respiratory disease.Conclusions:Both ambient and household air pollution have a deleterious pulmonary effect on long-term women residents of a representative urban slum in Delhi.

Background: Cooking and heating with solid fuels produces high levels of household air pollution (HAP) and is a substantial contributor to the disease burden. This study assesses the sources, magnitudes, and chemical compositions of HAP in traditional Eastern Tibetan Plateau households; examines the perturbation of urine metabolome in response to the HAP exposure; and explores how these correlate with cookstove use, fuel type, cooking behaviors, and residents' overall health.Methods: We measured 24-hour personal exposure to PM2.5 (n = 46) and kitchen area black carbon (BC) concentrations (n = 8), using MicroPEM and microAeth, respectively. We also measured particle-bound polycyclic aromatic hydrocarbon (PAH) (n = 12) and metal concentrations (n = 11) during post-analysis of the MicroPEM filter. We conducted household surveys (n = 24) regarding demographics, cookstove usage, fuel type, cooking behavior, and lifestyles. In addition, we collected fasting urine (n= 46) and applied untargeted metabolite profiling to monitor metabolic features and assess associations with measured HAP exposures. These data will be analyzed with bioinformatics approaches-Manhattan plot and Mummichog pathway analysis.Results: Our results reaffirm that burning firewood and yak dung, result in high PM2.5 and BC exposures. The geometric mean (95% CI) concentration was 92.2 (12.5, 682.4) μg/m3 for PM2.5 and the mean ± standard deviation (SD) concentration was 5.8 ± 5.5 μg/m3 for BC, 474.3 ± 584.3 ng/m3 for EPA standard suite of 16 PAHs, respectively. The mean ± SD of concentrations of twenty-five detected metal elements ranged from 0.9 ± 1.1 (Co) to 1585.1 ± 1621.5 ng/m3 (Si). Our statistical analyses illustrate high concentrations of PM2.5, BC, most PAHs and metals are significantly associated with village characteristics and household fuel types.Conclusion: Results from this study provide useful information for understanding the HAP exposure and related health risks in Tibetan communities.