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The burden of respiratory infections related to household air pollution
Neil W. Schluger, M.D.
Professor of Medicine, Epidemiology, and Environmental Health Sciences
Chief, Division of Pulmonary, Allergy and Critical Care Medicine
Columbia University
Household air pollution
• Approximately half the world’s population relies on combustion of biomass fuels (wood, dung, charcoal) for cooking and heating
• Exposure to biomass smoke is a major cause of illness and death in women and children
• Over 3 million deaths annually are attributed to household air pollution from biomass fuel use.
Deaths attributable to specific risk factors
Exposure Deaths
Air pollution 6.9 million
Ambient 3.4 million
Indoor 3.5 million
Tobacco use 6.3 million
Occupational exposures
0.85 million
Lim et al. Lancet 2012; 380: 2224-2260
Respiratory infections and HAP
• 2.8 million deaths per year worldwide from influenza and pneumonia
– Nearly 2 million are linked to household air pollution from biomass fuel burning
– The leading infectious cause of death in children age 0-5 years
• 1.5 millions deaths from tuberculosis
– 22% of these deaths may be related to household air pollution from biomass fuel burning
Lonnroth et al. Lancet 2010; 375: 1814-1829
Indoor air pollution is linked a high percentage of deaths from acute respiratory infections
Source: Schluger N. Acute Respiratory Infections Atlas
Indoor air quality in Addis Ababa
• Efficiency of traditional stoves is only 15%
• Household air levels of PM2.5 far exceeded recommended standards:
– Overall average level was 818 cg/m3 in 24-hour period
• U.S. EPA standard = 12gm/m3
• WHO standard = 10 gm/m3
• Delhi, the world’s most polluted city, has an average level of 153 gm/m3
Sanbata, Asfaw and Kumie. Atmosph Environ 2014; 89: 230-234WHO Air Quality Report 2014
8
• Collaboration between
Kintampo Health
Research Centre and
Columbia University.
• Women live in rural
areas; nonsmokers;
primary cooks for their
households.
• Mostly outdoor
cooking.
Kintampo, Ghana
Ghana Randomized Air Pollution Health
Study (GRAPHS): NIH R01 ES019547
9
Critical questions• How clean is clean enough…
– what interventions will get us there…
– and what distribution strategies will deliver equitable,
enduring public health results?
• Our study is designed to provide
– Evidence on the efficacy of stoves delivered to
pregnant women (a scalable distribution strategy)
– Exposure response data for birth weight and child
pneumonia
– Relevant evidence for the Government of Ghana
(where to invest: efficient biomass cookstoves or
clean fuels?)
10
Cluster-randomized 3-arm RCT – n = 1413 mother-infant
pairs3-stone fire (Control)
LPGBioLiteTM
11
Study hypotheses
Use of improved cook stoves before 3rd trimester of
pregnancy will lead to:
– a significant increase in average birth
weight in newborns.
– a significant reduction in the rate of
physician-assessed severe pneumonia
during the first 12 months of life.
12
Current status
– Pneumonia follow up ends in March 2016
– Currently analyzing birth weight and exposure data (follow-up
ended in December 2015)
– Pending proposals to follow cohort to examine the effects of early
life HAP exposures on cognitive outcomes and on lung function
trajectories
What we’ve learned (so far…)
– LPG is feasible but expensive in remote rural areas.
– Exposure reduction benefits of biomass cookstove are small;
LPG is more significant, but still smaller than expected.
– For LPG at least, we attribute this to “community air pollution” –
emissions from neighbors who continue to cook traditional fuels
attenuate the effect of the intervention stove.
– Central challenge, still unanswered: what cooking
technologies and intervention strategies will deliver lasting
exposure reductions to the very poor?
Household Air Pollution and Child Lung Health: Evidence from GRAPHS
Alison Lee, MD
+ Maximal Level of FEV1 (%)
50-
25-
100-
Symptoms
Disability
Age (Years)25 50 7550
-Genetics
-Environmental
factors
-Tobacco
Smoke
-Air Pollution
-Nutrition
-Infections
Lung function (FEV1) over the lifecourse. Lung function may be reduced at birth due to in utero
environmental factors such as household air pollution. Lung function “tracks” throughout
childhood, therefore impaired early life lung function may result in reduced maximally attainable
FEV1, a strong risk factor for the development of subsequent respiratory disease such as COPD.
75-
+Fetal Respiratory Development
Kajekar R. 2007. Pharmacol Therap 114:129–145
+Lung Function “Tracks”
Stern et al. Lancet 2007; 370: 758-64
+Air Pollution and Lung Development
in Children
Gauderman et al. NEJM 2015;
372: 905-13
+Window of Susceptibility to Air Pollution
Hsu et al. AJRCCM
2015;192(9):1052-
1059
+Evidence from GRAPHS
▶ Nested Lung Development Study– Infant Lung Function
• Preliminary Analyses (n=182), increased prenatal HAP exposure associated with:
– Reduced tidal volume
– Increased minute ventilation
– Impaired expiratory flow parameter
– Cord Blood and Placenta Samples
▶ GRAPHS Follow-Up– GRAPHS children through age 6– GRAPHS adult women
Joshua Rosenthal, Ph.D.
Fogarty International Center, NIH
Pneumonia Innovations Webinar Jan 29, 2016
By 2020 we need to be able to answer the questions:
• Under what conditions can a clean cooking intervention make a difference in health at the population scale?
– How and where can we make an effective intervention?
– How clean is clean enough?
– Which health parameters are most likely to improve?
And we must improve the capacity of LMIC scientists to answer these locally
1. Major reductions (clean fuels) necessary
2. Stove and fuel stacking in homes are the norm
3. Ambient conditions, heating, lighting and other confounders abound
4. You have to measure it!
Adapted from Clark et al 2013
Exposure Assessment: How clean is clean enough?
Major NIH Household Air Pollution Investments
Stove and fuel development and distribution• DOE + EPA + CDC• GACC + private sector• USAID + Intl grants and credits
Adoption and Behavior changeNIEHS R01 – Adoption study associated with Ghana Outcome trialImplementation Science Network (FIC/USAID/NCI) – Best practice case studies and evaluation of behavior in distribution efforts
Exposure and Toxicity EvaluationNIEHS R01 – Cookstove emissions profiles and subclinical effectsNational Toxicology Program (NIEHS) Assessment of aromatic compounds (PACs) polycyclic in cookstove smoke
Research Capacity-building• GEOHealth Hubs (FIC/NIEHS/NCI/ NIOSH/IDRC/GACC) – networked US and foreign institutional partnerships for research and training in
epidemiology, exposure science, experimental design, data management
Biomarker developmentOngoing relevant research by NIEHS, NCI, NHLBI, NICHDTargeted NIH activity in development
Health Outcomes – Proof of Principle Controlled TrialsNIEHS R01s – Ghana, Nepal (maternal and child health results in 2016 and 2017)Targeted NIH-GACC-GACD + Outcomes Trial initiative in development
Field Evaluation of Stove Distribution• NIEHS R01 – Cooperative evaluation of private sector stove distribution program on exposure and public health measures in Rwanda
FY 2014 2015 2016
NIH, BMGG, GACC Partnership - $30M, 5 year Interventional Trial – 3-5 Countries on coordinated protocol. “Smoke free” homes vs controls.
Carefully monitored behaviors, exposures and health outcomes
Objectives: Response curves for PM 2.5 and maternal morbidity, infant mortality, under 5 ALRI, LBW, Asthma and indicators for other chronic diseases (e.g. COPD, Lung Cancer)
HAP Health Outcomes Trial
Implementation Science Network 20-25 scientists including site PIs
and Implementers
SouthAsia
National
ProjectedCurrent
HAP trans-NIH Intervention Trial
Biomarker developmentLatin
America NIH R01
Africa NIH R01
East Asia
Others
Trial site
Trial siteTrial site
AfricaUSAID
Latin AmericaC
DC
NIH Awarded
NIH Common Fund
Partner agencies
Trans-NIH HAP
Other funder
Clean Cooking Implementation Science
Network
AIM: Advance knowledge and tools on where and how uptake and sustained use is most likely to succeed
• Trans-NIH Activity with USAID, CDC, and GACC and others
• Evaluation of policy, program context and behavior in clean fuel distribution programs
• Contextualized guides: best practices and pre-conditions
25
Accelerating the
Child Health
Benefits of
Scaling Up Clean
Cooking
Sumi Mehta, MPH, [email protected]
Pneumonia Innovations Webinar | January 29, 2016
| C L E A N C O O K S T O V E S A N D F U E L S 26
More and more clean stoves and fuels are
being distributed (and tracked) each year
Clean Fuels are Central to Addressing Ensuring Public
Health Benefits
Solar / Electricity
Clean cooking is increasingly within reach
• LPG, ethanol, biogas, electricity within reach for hundreds of millions
• First Tier 4 biomass pellet stove now available and in the field, with capacity to produce at scale (2000/day)
Challenge: increasing access and affordability
Credible International Standards Development Bodies Inform Definition of ‘Clean’
Tier 4* for ‘indoor emissions’ will likely achieve the greatest health benefits
| C L E A N C O O K S T O V E S A N D F U E L S 27
• Much of earlier research did not focus on very clean stoves
• Emerging results are promising
– women like using clean fuels, and use them near
exclusively when possible
– drastic reductions in exposure to air pollution have been
measured
Efficacy Effectiveness: Challenges are not unique to
clean cooking interventions!
– Coverage
– Competing risk factors
– Behavior change communication
Are We Getting Clean Enough to Impact Child Survival?
| C L E A N C O O K S T O V E S A N D F U E L S 28
Public Health Imperative: Ensuring Adoption of Clean Cooking Saves Lives
Strong Progress & Future Opportunities to Accelerate Clean Fuels to Scale
Alliance and Partners will Continue Efforts to Strengthen Markets and Support Advocacy
• Investment Opportunities
– Pipeline strengthening:
• R&D to better meet cooking needs
(reducing costs, increasing durability)
• facilitating consumer financing
• increasing production capacity
– Innovations to accelerate distribution
• smaller LPG cylinders
• portable filling stations
• pay as you go etc.
– Under development (late 2016): Gold Standard Foundation methodology on health RBF for clean cooking
• Transformation of government subsidies to expand access and affordability at the base of the pyramid
– India Give it Up Campaign for LPG
– Opportunity: Nigeria kerosene subsidy
– Opportunity: Clean fuels in China
| C L E A N C O O K S T O V E S A N D F U E L S 29
WANTED!Collaborators to mainstream clean cooking into
ongoing Pneumonia prevention efforts
• Help increase awareness through existing public
health channels
• Integrate clean cooking into existing distribution
networks / Implementation
Accelerated progress on child survival
REWARD