Background Household air pollution from solid fuels increases the risk of childhood pneumonia. Nasopharyngeal carriage of Streptococcus pneumoniae is a necessary step in the development of pneumococcal pneumonia. We aimed to assess the association between exposure to household air pollution and the prevalence and density of S pneumoniae carriage among children. Methods The Malawi Streptococcus pneumoniae Carriage and Air Pollution Exposure study was a nested, prospective, observational study of children participating in the cluster randomised controlled Cooking and Pneumonia Study (CAPS) in the Karonga Health and Demographic Surveillance System (HDSS) area in northern Malawi. CAPS compared the effects of a cleaner burning biomass-fuelled cookstove (intervention group) with traditional open-fire cooking (control group) on the incidence of pneumonia in children. Eligible children aged 6 weeks or 6 months (those recruited a 6 weeks were also followed up at age 6 months) were identified by the Karonga HDSS centre. Nasopharyngeal swabs were taken to detect S pneumoniae , and infant exposure to particulate matter with a diameter of <= 2.5 mu m (PM2.5) exposure was assessed by use of a MicroPEM device. The primary outcome was the prevalence of nasopharyngeal S pneumoniae carriage in all children aged 6 months, assessed in all children with valid data on PM2.5. The effects of the intervention stoves (intention-to-treat analysis) and PM2.5 (adjusted exposure-response analysis) on the prevalence of S pneumoniae carriage were also assessed in the study children. Findings Between Nov 15, 2015, and Nov 2, 2017, 485 children were recruited (240 from the intervention group and 245 from the control group). Of all 450 children with available data at age 6 months, 387 (86% [95% CI 82-89]) were positive for S pneumoniae. Geometric mean PM2.5 exposure was 60.3 mu g/m(3) (95% CI 55.8-65.3) in S pneumoniae- positive children and 47.0 mu g/m(3) (38.3-57.7) in S pneumoniae-negative children (p=0.044). In the intention-to-treat analysis, a non-significant increase in the risk of S pneumoniae carriage was observed in intervention group children compared with control group children (odds ratio 1.36 [95% CI 0.95-1.94]; p=0.093). In the exposure-response analysis, a significant association between PM2.5 exposure and S pneumoniae carriage was observed; a one unit increase in decile of PM2.5 was found to significantly increase the risk of S pneumoniae carriage by 10% (1.10 [1.01-1.20]; p=0.035), after adjustment for age, sex, 13-valent pneumococcal conjugate vaccination status, season, current use of antibiotics, and MicroPEM run-time. Interpretation Despite the absence of effect from the intervention cookstove, household air pollution exposure was significantly associated with the prevalence of nasopharyngeal S pneumoniae carriage. These results provide empirical evidence for the potential mechanistic association between exposure to household air pollution and childhood pneumonia. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd.

Background: Household air pollution (HAP) from solid cooking fuels is a risk factor for childhood pneumonia. Nasopharyngeal carriage of Streptococcus pneumoniae is a necessary step in development of pneumococcal pneumonia. We hypothesised that HAP influences S. pneumoniae carriage. MSCAPE assesses the relationship between HAP from solid cooking fuels and prevalence/density of S. pneumoniae carriage among children. Methods: MSCAPE is a prospective study of children participating in a trial of a cleaner burning cookstove to reduce childhood pneumonia incidence in Malawi (CAPS). MSCAPE assessed the impact of HAP exposure on prevalence of S. pneumoniae carriage in 6 week and 6 month old children through intention-to-treat and adjusted exposure-response analyses. Exposure to HAP (PM2·5) was assessed through RTI Micropem and S. pneumoniae detection in nasopharyngeal swabs. Findings: S. pneumoniae carriage prevalence was 39% (n=89) and 85% (n=398) in 6 week and 6 month old children respectively. A higher mean PM2·5 exposure was observed in intervention children (53·9 µg/m3) than controls (49·0 µg/m3), although not significant (p>0.05). Intention-to-treat analysis found a non-significant increased risk of S. pneumoniae carriage in intervention children (OR=1·36; 95% CI:0·97, 1·92). Exposure-response analysis found a significant association between HAP exposure and S. pneumoniae carriage with a 10% increase in risk per decile of PM2·5 exposure (OR=1·10; 95% CI:1·01, 1·20, p=0·035). Interpretation: Despite the lack of observed impact from the cleaner burning cookstove intervention, HAP exposure (PM 2·5) was significantly associated with S. pneumoniae prevalence giving empirical evidence for the potential mechanistic relationship between HAP and childhood pneumonia. Funding Statement: This work was supported by Bill and Melinda Gates Foundation through grant number OPP1131425. The CAPS was funded by a Joint Global Health Trials Grant from the Medical Research Council, the UK Department for International Development and Wellcome Trust (MR/K006533/1). Declaration of Interests: There are no financial competing interests in relation to the work described. Ethics Approval Statement: Ethical approval was provided by the College of Medicine Research and Ethics Committee (COMREC), Malawi (P.08/15/1794) and the Central Ethics Committee of the University of Liverpool (RETH000839).

Globally, approximately 3 billion primarily cook using inefficient and poorly vented combustion devices, leading to unsafe levels of household air pollution (HAP) in and around the home. Such exposures contribute to nearly 4 million deaths annually (WHO 2018a, 2018b ). Characterizing the effectiveness of interventions for reducing HAP concentration and exposure is critical for informing policy and programmatic decision-making on which cooking solutions yield the greatest health benefits. This review synthesizes evidence of in-field measurements from four cleaner cooking technologies and three clean fuels, using field studies aimed at reducing HAP concentration and personal exposure to health damaging pollutants (particulate matter (PM2.5) and carbon monoxide (CO)). Fifty studies from Africa, Asia, South and Latin America, provided 168 estimates synthesized through meta-analysis. For PM2.5 kitchen concentrations, burning biomass more cleanly through improved combustion stoves (ICS) with (n = 29; 63% reduction) or without (n = 12; 52%) venting (through flue or chimney) and through forced-draft combustion (n = 9; 50%) was less effective than cooking with clean fuels including ethanol (n = 4; 83%), liquefied petroleum gas (LPG) (n = 11; 83%) and electricity (n = 6; 86%). Only studies of clean fuels consistently achieved post-intervention kitchen PM2.5 levels at or below the health-based WHO interim target level 1 (WHO-IT1) of 35 μg m−3. None of the advanced combustion stoves (gasifiers) achieved WHO-IT1, although no evidence was available for pellet fuelled stoves. For personal exposure to PM2.5, none of the ICS (n = 11) were close to WHO-IT1 whereas 75% (n = 6 of 8) of LPG interventions were at or below WHO-IT1. Similar patterns were observed for CO, although most post-intervention levels achieved the WHO 24 h guideline level. While clean cooking fuel interventions (LPG, electric) significantly reduce kitchen concentrations and personal exposure to PM2.5 in household settings, stove stacking and background levels of ambient air pollution, have likely prevented most clean fuel interventions from approaching WHO-IT1. In order to maximize health gains, a wholistic approach jointly targeting ambient and HAP should be followed in lower-and-middle income countries.

The World Health Organisation (WHO) Global Age-Friendly Cities (AFC) Guide classifies key characteristics of an AFC according to eight domains. Whilst much age-friendly practice and research have focused on domains of the physical environment, those related to the social environment have received less attention. Using a Photovoice methodology within a Community-Based Participatory Research approach, our study draws on photographs, interviews and focus groups among 26 older Liverpool residents (60+ years) to explore how the city promotes respect and social inclusion (a core WHO AFC domain). Being involved in this photovoice study allowed older adults across four contrasting neighbourhoods to communicate their perspectives directly to Liverpool's policymakers, service providers and third sector organisations. This paper provides novel insights into how: (i) respect and social inclusion are shaped by aspects of both physical and social environment, and (ii) the accessibility, affordability and sociability of physical spaces and wider social processes (e.g., neighbourhood fragmentation) contributed to or hindered participants' health, wellbeing, intergenerational relationships and feelings of inclusion and connection. Our findings suggest that respect and social inclusion are relevant across all eight domains of the WHO AFC Guide. It is core to an AFC and should be reflected in both city-based policies and evaluations.

PDS 64: Health impact assessment and environmental justice, Johan Friso Foyer, Floor 1, August 26, 2019, 1:30 PM - 3:00 PM Background: Purchasing start-up equipment for cooking with LPG represents a key barrier to adoption in resource-poor settings. To address this barrier, a micro-finance package for LPG (double burner, cylinder and accessories) was introduced in Cameroon, and offered to 150 households on a first-come, first served basis, repayable over 6 months at no interest. We evaluated the perceived impact on LPG adoption by a peri-urban community in South-West Cameroon. Methods: One to 2 months after receiving the equipment, semi-structured interviews (SSIs) were conducted with 10 purposively selected participants: 5 households that took the loan (beneficiaries) and 5 households that had not taken the loan (non-beneficiaries), investigating the decision-making process surrounding the loan and cooking practices. After 6 months, we conducted SSIs with 10 additional beneficiaries, exploring experiences of loan repayments and how LPG use impacted on daily life. To generate discussion around the micro-loan and cooking patterns, we conducted a focus group with participants (n=8) sampled from the above groups. Transcripts were analysed thematically. Results: Beneficiaries reported that the loan allowed them to purchase the start-up equipment, which they would not have been able to afford otherwise. Monthly payments made the loan more affordable to beneficiaries and attractive to non-beneficiaries. Beneficiaries described that cooking with LPG improved their lives, through reduced smoke, better health and time savings. They reported cooking most dishes with LPG almost daily, including traditional meals, and LPG use increased during the rainy season. Conserving LPG was the main reason for continued use of biomass. Although 94% of beneficiaries (n=141) repaid the loan, some struggled to pay on time. Suggestions for improvement included a three/four-burner stove to accommodate multiple dishes. Conclusions: Through qualitative methods, we gained unique insights into the facilitators/inhibitors surrounding the loan, and benefits of LPG. Findings are informing further LPG microloan initiatives across Cameroon.

Recent years have seen a proliferation of initiatives aimed at enhancing the age-friendliness of urban settings. The World Health Organization’s (WHO) global Age-Friendly Cities (AFC) programme has been central to these. Cities seeking to become more age-friendly need reliable ways of assessing their efforts. This article describes an evidence-based evaluation tool for age-friendly initiatives whose development was informed by fieldwork in Liverpool/UK. The tool complements existing assessment frameworks, including those provided by WHO, by paying particular attention to the structures and processes underlying age-friendly initiatives. It reflects the complexity of age-friendliness by reconciling a focus on breadth with detail and depth, and it allows for a highly accessible visual presentation of findings. Using selected examples from Liverpool, the article illustrates how the evaluation tool can be applied to guide policy and practice with an age-friendly focus in different urban contexts. Pilot testing in further settings is underway to refine the tool as a practical method for evaluation and for supporting city-level decision making.

Approximately four million people die each year in low- and middle-income countries from household air pollution (HAP) due to inefficient cooking with solid fuels. Liquid Petroleum Gas (LPG) offers a clean energy option in the transition towards renewable energy. This qualitative study explored lay knowledge of barriers and facilitators to scaling up clean fuels in Cameroon, informed by Quinn et al.'s Logic Model. The model has five domains and we focused on the user and community needs domain, reporting the findings of 28 semi-structured interviews (SSIs) and four focus group discussions (FGDs) that explored the reasons behind fuel use choices. The findings suggest that affordability, safety, convenience, and awareness of health issues are all important influences on decision making to the adoption and sustained use of LPG, with affordability being the most critical issue. We also found the ability of clean fuels to meet cooking needs to be central to decision-making, rather than an aspect of convenience, as the logic model suggests. Local communities provide important insights into the barriers and facilitators to using clean fuels. We adapt Quinn et al.'s logic model accordingly, giving more weight to lay knowledge so that it is better positioned to inform policy development.

Each year up to 2.6 million people die prematurely from household air pollution (HAP) due to cooking with polluting fuels such as wood and charcoal, particularly in low and middle-income countries (LMICs). The World Health Organisation recommends scaling the adoption of clean fuels to improve maternal and child health. Liquefied Petroleum Gas (LPG) represents a scalable clean fuel that provides health and environmental benefits when used for household energy in LMICs. In Cameroon, over 70% of people rely on biomass for cooking, and the Government aims to increase LPG use from < 20% to 58% by 2030. Supporting households make this transition requires involvement of multiple stakeholders and an understanding of perspectives from the community's perspective. We used visual participatory methods `Photovoice' to explore households' perceptions of factors influencing the uptake of LPG for cooking in South-West Cameroon. Two groups of participants from rural (n = 7) and peri-urban (n = 8) areas photographed subjects they identified as preventing and facilitating LPG uptake in their communities. Subsequently, individual interviews (n = 15) and group discussions (n = 5) explored participants' reflections on the photographs. Thematic analysis was conducted using NVivo 10 software. The main barriers identified included difficulty in affording the initial LPG equipment and ongoing refills, scarcity of LPG retail shops and refills, and safety concerns. Facilitators included (i) increasing awareness of the benefits of LPG (e.g. health), (ii) increasing retail outlet density in rural areas, (iii) addressing safety concerns (e.g. replacing damaged cylinders), and (iv) reducing the price of LPG refills. Participants presented their photos at a public exhibition, which generated discussions with key stakeholders (e.g. government ministries) about how best to assist communities in this transition. Photovoice was found to be an innovative and effective approach for exploring how to advance equitable access to LPG from a community perspective and successfully engage with key stakeholders.

Background: Most households in Cameroon rely on solid fuel for cooking. The government haslaunched a Master Plan to increase LPG use from <20% to 58% by 2035 to address deforestationand energy security issues. To understand how to support communities transition from solid fuelto LPG, LACE surveys assessed household characteristics and perceptions of LPG in different fuelusing groups.Methods: After rapid census, 320 households from rural and peri-urban communities in SWCameroon were randomly selected into 4 fuel-use groups: exclusive LPG (n=51), primary LPG(n=52), mixed LPG and biomass (n=113) and exclusive wood (n=104). Surveys collectedinformation on (i) household characteristics and fuel use practices, (iii) perceptions of LPG and (iv)experience of health issues and burns.Results: Amongst LPG users, distance from retailer (refills) impacted on more exclusive use (travel> 5km: 15% of LPG exclusive/ primary users vs 24% of LPG mixed). Greater income, education anda younger age were associated with increasing LPG use (p<0.05). Perceptions of LPG as a cookingfuel differed by amount of LPG use. 85% of LPG exclusive users reported LPG could be used formost foods compared to 40% of wood exclusive users (p<0.05). Increasing LPG use was associatedwith increased reporting of LPG as a clean and fast fuel and cost was less of an issue. In all groups,LPG was perceived as potentially dangerous (>75% reporting). The occurrence of cough andphlegm was low in all groups, whilst a higher proportion of exclusive wood users reported soreeyes (60% vs 29% (LPG exclusive) p<0.005) and burns (23% vs 10% p=0.007) .Conclusion: Potential barriers to adoption and more exclusive use of LPG include its perceivedability to cook most foods, perceptions over its safety and distance from retail outlets. Householdincome is a strong indicator of usage. Education strategies (health and safety) and financialsupport mechanisms (e.g. microfinance) could help scaling LPG adoption

Background: Cameroon relies on biomass fuel (mainly wood) for cooking, (88% rural population), with important health, deforestation and climatic consequences. The Government aims to increase Liquified Petroleum Gas (LPG) use from < 20% to 58% of the population by 2035 and developed a Masterplan (2016) to achieve this goal via a multi-sectoral committee (ministries, national agencies, private sector and the Global LPG Partnership). An Investment Committee was established to oversee implementation. Objectives: To document and evaluate the Cameroon national process for LPG scale-up. Methods: The RE-AIM framework structured data collection and reporting: secondary data (socio-economic development, energy situation, policy); Masterplan documentation; LPG market expert and national stakeholder interviews; and LPG Adoption in Cameroon Evaluation (LACE) study data (community data on fuel use, stacking, barriers to LPG use, microloan schemes, impacts on particulate air pollution (PM2.5) and health). A logic model compared Masterplan proposals with issues reported by users and stakeholders. Findings: Masterplan recommended: €400 million investment to 2030 to increase LPG cylinders by 7 million, infrastructure developments (storage, transport, distribution and retail facilities), enhanced market regulation, national harmonisation of refill price and cylinder import tax reductions. The LACE studies highlighted user concerns about costs, safety, access, supply and cooking traditional foods. Stakeholders proposed increasing microfinance initiatives, LPG promotion, user support and health system engagement to promote clean fuels. Conclusions: The Masterplan has the potential to address problems of LPG access and supply and improve industry safety. Microfinance is supported and new pricing arrangements may lower cylinder deposit costs. Users' concerns (affordability, access, safety, traditional cooking) need consideration. Programme monitoring and evaluation is recommended.

Approximately 3 billion people, most of whom live in Asia, Africa, and the Americas, rely on solid fuels (i.e. wood, crop wastes, dung, charcoal) and kerosene for their cooking needs. Exposure to household air pollution from burning these fuels is estimated to account for approximately 3 million premature deaths a year. Cleaner fuels – such as liquefied petroleum gas, biogas, electricity, and certain compressed biomass fuels – have the potential to alleviate much of this significant health burden. A wide variety of clean cooking intervention programs are being implemented around the world, but very few of these efforts have been analyzed to enable global learning. The Clean Cooking Implementation Science Network (ISN), supported by the U.S. National Institutes of Health (NIH) and partners, identified the need to augment the publicly available literature concerning what has worked well and in what context. The ISN has supported the development of a systematic set of case studies, contained in this Special Issue, examining clean cooking program rollouts in a variety of low- and middle-income settings around the world. We used the RE-AIM (reach, effectiveness, adaptation, implementation, maintenance) framework to coordinate and evaluate the case studies. This paper describes the clean cooking case studies project, introduces the individual studies contained herein, and proposes a general conceptual model to support future planning and evaluation of household energy programs.

In 2016, the government of Cameroon, a central African country heavily reliant on wood fuel for cooking, published a Masterplan for increasing primary use of LPG from 20% to 58% of households by 2035. Developed via a multi-sectoral committee with support from the Global LPG Partnership, the plan envisages a 400 million Euro investment program to 2030, focused on increasing LPG cylinder numbers, key infrastructure, and enhanced regulation. This case study describes the Masterplan process and investment proposals and draws on community studies and stakeholder interviews to identify factors likely to impact on the planned expansion of LPG use.

IntroductionCameroon has begun implementation of a national liquified petroleum gas (LPG) Master Plan to increase use of LPG from <20% to 58% of the population by 2030 to address the environmental and health impacts of reliance on solid fuel for domestic energy. The LPG Adoption in Cameroon Evaluation (LACE) studies assessed the potential impacts of replacing traditional solid cooking fuel with LPG on household air pollution (HAP) and personal exposures.MethodsSamples of households (exclusive wood fuel (n=61) and primary LPG fuel (n=67)) from peri-urban and rural households in South West Cameroon were identified from LACE census surveys. PM2.5 was measured over a 48-hr period using the RTI MicroPEM for kitchens (n=55; n=67), women cooks (n=61; n=67) and children (n=56; n=60). Stove-use-monitoring data, demographic and health surveys, and time activity diaries were collected alongside the exposure measurements.ResultsKitchen PM2.5 concentrations were significantly lower in households using LPG as their primary fuel compared to those using wood (geometric mean (GM) 23.7 vs 391.5 µg/m3 p<0.0005). In addition, exposures in women (GM=14.5 vs 52.3 µg/m3 p<0.0005) and children (GM=11.6 vs 29.9 µg/m3 p<0.0005) were significantly lower in LPG households. Exclusive use of LPG was associated with the lowest levels of PM2.5 for kitchens (exclusive =18.5 vs mixed=28.7 µg/m3), women (exclusive=13.3 vs mixed=15.9 µg/m3) and children (exclusive=11.1 vs mixed=12.0 µg/m3).ConclusionWe measured significant reductions in mean PM2.5 kitchen concentrations and personal exposure levels in households primarily using LPG when compared to those exclusively burning wood. Mean kitchen and personal PM2.5 concentrations were lower than the annual WHO interim-target 1 guideline level of 35 µg/m3. These results show that a targeted effort to promote clean fuel adoption on a national level has the potential to significantly decrease HAP exposures of the most vulnerable populations.

Background/Aim: Around 3 billion people globally rely on solid fuels for their everyday household cooking. The resultant household air pollution (HAP) causes childhood pneumonia. Streptococcus pneumoniae (SP) is the most important causative organism, and naso-pharyngeal carriage (NPC) is considered as a key step in acquiring pneumonia. Very little is known about the association of HAP with NPC. This study aims to investigate the effect of HAP reduction on NPC. Methods: The study was carried out at the Karonga Prevention Study, Malawi, where children born in homes with improved stoves and open fire were followed at 6 weeks and 6 months. Nasal swabs of children were obtained for culture and Lyt-A PCR and 48-hr PM2.5 exposure were measured using the innovative RTI MicroPEM. Data on households, family, and vaccination status were obtained through interview and records. Results: The personal exposure measurements and nasopharyngeal carriage are available on 694 children. The incidence of SP carriage was 39% at six week and prevalence of SP carriage was 85% at 6 months of age. The average PM2.5 exposure was significantly higher for 6-month old children (57.8µg/m3, 95%CI:53.8, 62.0) compared to 6-week old children (40.2µg/m3, 95%CI:36.4,44.4); p<0.0001). For 6-month old children, the mean exposure of PM2.5 was higher among SP positive children compared to SP negative children (60.6 µg/m3 vs 43.4 µg/m3; p=0.002). Logistic regression analysis indicates that the exposure to PM2.5 in 6 month old children is significantly associated with NPC (OR:3.7; 95%CI:1.6-8.5). Conclusions: To our knowledge this is the first report showing the relationship between PM2.5 exposure and SP carriage in young children. NPC is a necessary step leading to pneumonia in children and higher prevalence of NPC may indicate the pathway through which HAP causes pneumonia in young children. Further research is required to elucidate the mechanism of HAP facilitating the NPC.

Many interventions have been developed to promote respect and social inclusion among older people, but the evidence on their impacts on health has not been synthesised. This systematic review aims to appraise the state of the evidence across the quantitative and qualitative literature.

Background: Each year up to 4 million people die prematurely from household air pollution due to domestic use of solid fuel, mainly in low and middle-income countries (LMICs). Liquefied Petroleum Gas (LPG) is an affordable, scalable, and widely available clean fuel that provides health and environmental benefits when used for household energy in LMICs. In Cameroon, where 70% of people rely on biomass for cooking, the Government aims to increase LPG use from < 20% to 58% by 2035. Few qualitative studies have explored households' perceptions of factors affecting LPG uptake. We conducted community-based participatory research using photovoice methods to explore factors influencing LPG uptake and sustained use in South-West Cameroon. Methods: Two groups of participants from rural (n=7) and peri-urban (n=8) areas photographed aspects of their lives which prevented/enabled LPG uptake in their communities. Individual interviews (n=15) and group discussions (n=5) explored participants' reflections on the issues photographed. We conducted thematic analysis using NVivo 10 software. Results: Main barriers included difficulty in affording the initial LPG equipment and ongoing refills, scarcity of LPG retail shops and safety concerns. Key enablers/solutions included (i) increasing awareness of the benefits of LPG, (ii) additional retail shops, (iii) addressing safety concerns, (iv) repairing roads to improve distribution, and (v) reducing the refill price. We organised an exhibition of participants' photos to generate discussions between participants and representatives from government, communities, industry and media about how to assist communities with fuel transition. Conclusions: Photovoice was found to be an effective participatory approach that (i) identified factors affecting uptake and use of LPG, which could be transferable to Sub-Saharan contexts, and (ii) engaged with participants and key stakeholders to identify how to advance equitable access to LPG in Cameroon.

Currently 70% of the population in Cameroon are reliant on solid fuel for cooking (90% in rural communities) and the associated household air pollution contributes to significant mortality and morbidity in the country. To address the problems of energy security, deforestation and pollution the government has developed a strategy (Masterplan) to increase use of liquified petroleum gas (LPG) as a cooking fuel from 12% to 58% by 2030. As a clean fuel scaled adoption of LPG has the potential to make significant positive impacts on population health. The LPG Adoption in Cameroon Evaluation (LACE) studies are assessing in the community (i) barriers and enablers for and (ii) local interventions to support, adoption and sustained use of LPG. A census survey conducted for LACE in rural and peri-urban regions of SW Cameroon provided an opportunity to investigate current fuel use patterns and factors associated with primary and exclusive use of LPG. A cross-sectional survey of 1577 households (1334 peri-urban and 243 rural) was conducted in March 2016 using standardised fuel use and household socio-demographic questions, administered by trained fieldworkers. Wood (40.7%) and LPG (51.1%) were the most frequently reported fuels, although the dominant fuels in rural and peri-urban communities were wood (81%) and LPG (58%) respectively. Fuel stacking was observed for the majority of LPG using households (91% of peri-urban and 99% of rural households). In rural homes, a higher level of education, access to sanitation and piped water and household wealth (income and asset ownership) were all significantly associated with LPG use ( p < 0.05). In peri-urban homes, younger age, access to sanitation and piped water and increasing education were significantly associated with both any and exclusive use of LPG ( p < 0.05). However, whilst household wealth was related to any LPG use, there was no relationship with exclusive use. Results from this census survey of a relatively well-established LPG market with lower levels of poverty and high levels of education than Cameroon as a whole, find LPG usage well below target levels set by the Cameroon government (58% by 2030). Fuel stacking is an issue for the majority of LPG using households. Whilst, as observed here, education, household wealth and socio-economic status are well recognised predictors of adoption and sustained use of clean modern fuels, it is important to consider factors across the whole LPG eco-system when developing policies to support their scaled expansion. A comprehensive approach is therefore required to ensure implementation of the Cameroon LPG Masterplan achieves its aspirational adoption target within its stated timeframe.

Background Psychological distress (PD) (mental ill-health) has a frequency between 5 and 25% in urban populations, and there is mounting evidence that access to green space might reduce its occurrence. Evidence suggests that the quality of green space is as important as accessibility in promoting mental well-being. A pilot study for EURO-URHIS 2 allowed investigation of access to green space in relation to PD in a deprived urban population in the UK. Methods An adult urban health indicator questionnaire, including the GHQ-12 and validated questions on access to and quality of green space, was sent to a stratified random sample of 1680 adults drawn from one general practice list in Sandwell, UK. Multivariable logistic regression was used to determine associations between attributes of green space and PD adjusting for age, sex and levels of deprivation. Results There were 578 (35%) completed responses. The reported prevalence of PD [n = 131 (22.7%)] was significantly greater than national England and Wales estimates. As well as accessibility (OR = 0.58; 95% CI = 0.35, 0.96) and sufficiency (OR = 0.12; 95% CI = 0.39, 0.89) of green spaces, having the ability to use them for relaxation and recreation were significantly associated with reduced PD [OR = 0.13 (0.42, 0.94) and OR = 0.11 (0.34, 0.80), respectively]. In addition, a dose-response relationship between number of positive green space attributes and PD was identified (P < 0.05). Conclusion This population-based study in a deprived urban UK population demonstrates an association, and some dose-response relationship, between access to and quality of green spaces with reduced PD. The cross-sectional design and use of subjective measures limit interpretation of causality. More knowledge is needed on how UK planning affects green spaces and the potential mental health consequences.

IntroductionThe LPG Adoption in Cameroon Evaluation (LACE) studies aimed to identify and address barriers to adoption and use of liquified petroleum gas (LPG) as a clean fuel. This included evaluation of a microfinance scheme (paid back over 6 months) to fund an LPG start-up kit (stove, equipment and gas; US$95), a barrier to adoption identified by LACE. We report here impacts on fuel-use practices, household air pollution exposure, acute health symptoms and burns in loan beneficiaries.Methods110 beneficiaries completed household surveys prior to receiving the LPG start-up kit, and then again after the loan period. Additional surveys were completed by 500 households each from beneficiary and control communities. 48-hr PM2.5 samples (kitchen concentrations and cook exposures) were measured in 35 beneficiary households at the two data collection periods using the RTI MicroPEM.ResultsMost households repaid the loan (89%), although 41% reported difficulty making repayments. After the loan, primary fuel use changed from wood (75%) and other biomass (15%) to LPG (79%), although no households used LPG exclusively. Levels of PM2.5 declined from baseline to after the loan period for kitchen concentrations (geometric mean (GM) 337.9 µg/m3 vs 32.3 p<0.0005) and cook exposures (GM=73.8 µg/m3 vs 28.6 p<0.0005). Significant reductions in headaches (46% to 9%; p<0.0005), eye problems (66% to 8%; p<0.0005), cook burns (25% to 3%; p<0.0005) and child burns (9% to 0%; p<0.0005) were observed after the loan. An increase in primary use of LPG was observed in the beneficiary community (46% to 55%) not seen in controls (67% to 67%).ConclusionSuccesses of this loan pilot included (i) a high level of repayment and LPG use, (ii) reductions in household air pollution, self-reported health symptoms and burns and (iv) increased community adoption of LPG. Fuel stacking remains an ongoing issue. The pilot has informed a second phase involving 800 homes across five regions of Cameroon.