When the Land Became the Clue: Geospatial Insights into Chronic Bronchitis in Rural Mysuru, India
For decades, Karya was like any other quiet village in southern India. Life moved with the seasons. Fields turned green after the monsoon, smoke rose gently from kitchen hearths at dawn, and men left home early to work in nearby farms or local industries. Coughs were common, especially among older adults, but they were rarely a cause for alarm. Breathlessness, persistent phlegm, and night-long coughing were accepted as part of aging, smoking, or years of cooking with firewood.
Over time, however, something felt different.
More villagers complained that their cough never went away. Some struggled to breathe even while walking short distances. Others woke each morning choking on thick sputum. The illness had no dramatic outbreak, no sudden beginning, it crept in quietly, year after year, embedding itself into daily life.
What puzzled the villagers, and later the doctors, was a simple but troubling question:
Why was chronic bronchitis so common here, but almost absent in neighboring villages?
People smoked similar amounts. Women relied on the same biomass fuels. Occupations were comparable. Yet the suffering was not evenly shared.
From Local Suffering to a Scientific Question
This quiet mystery gained clarity when researchers from the Mysuru Studies of Determinants of Health in Rural Adults (MUDHRA) began systematically surveying villages across the Mysuru district of Karnataka. Using standardized, internationally validated questionnaires, they documented respiratory symptoms among adults aged 30 years and above.
As the data accumulated, a striking pattern emerged.
This stark contrast raised a fundamental epidemiological question:
If individual risk factors were similar, could the environment itself be shaping disease?
To answer this, the study moved beyond traditional survey-based epidemiology and entered the realm of spatial epidemiology, integrating health data with Remote Sensing (RS), Geographic Information Systems (GIS), satellite imagery, and field investigations.
Chronic Bronchitis as an Emerging Rural Public Health Challenge
Chronic bronchitis is a major clinical subtype of chronic obstructive pulmonary disease (COPD), defined by chronic cough and sputum production for at least three months in two consecutive years. While historically linked to tobacco smoking, it is now increasingly recognized as a disease shaped by environmental, occupational, and geographic determinants, particularly in low- and middle-income countries.
In India, chronic respiratory diseases contribute substantially to morbidity, disability, and premature mortality. Rural populations are especially vulnerable due to prolonged exposure to biomass fuels, dust, occupational hazards, and limited access to preventive healthcare. Yet, despite this vulnerability, spatial patterns of disease burden and environmental risk factors remain poorly explored in rural epidemiological studies.
The MUDHRA cohort provided a rare opportunity to address this gap by combining population-based health data with spatial environmental analysis.
Study Setting: Geography, Climate, and Environment
The region experiences a dry tropical to sub-tropical climate, with high summer temperatures, seasonal winds, and moderate rainfall. Agriculture dominates livelihoods, supported by the Cauvery and Kapila rivers. At the same time, parts of Nanjangud taluk host industrial and mining activities, introducing localized environmental stressors.
Subtle differences in elevation, wind direction, land-use patterns, and proximity to industrial sites, often invisible in conventional epidemiology, became evident through geospatial analysis.
The MUDHRA-CB Cohort: Population and Data Collection
Between 2006 and 2009, the MUDHRA-CB study surveyed 8,457 adults aged 30 years and above, achieving a response rate of 93%. Data were collected through door-to-door household surveys using the internationally validated Burden of Obstructive Lung Disease (BOLD) questionnaire, adapted into Kannada.
Participants were assessed for:
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Chronic bronchitis symptoms
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Smoking habits
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Biomass fuel exposure
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Occupational history
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Socioeconomic and demographic characteristics
All women in the cohort were exposed to biomass fuel, while smoking prevalence among men varied across villages. This created a shared baseline of known risk factors, allowing environmental differences to be examined more clearly.
Seeing What the Eye Could Not: Mapping Disease on the Land
When chronic bronchitis prevalence was plotted on village-level maps, the disease no longer appeared random. Instead, it clustered.
Karya emerged as a clear hotspot, while Alatthuru formed a coldspot. This spatial pattern suggested that place mattered.
Satellite imagery revealed a critical feature near Karya village: an active magnesite and dunite mining area located barely 310 meters from human settlements. From space, the mine appeared as a scar on the land, vegetation gradually replaced by bare earth, waste dumps, haulage roads, and crushing zones.
But maps alone were not enough.
Researchers walked the ground.
They observed continuous dust rising from crushers and trucks, coating roads, crops, rooftops, and homes. Fine particles lingered in the air, often invisible, yet persistent. Seasonal northeasterly winds during summer months carried this dust directly toward Karya village, aided by elevation differences that funneled airborne particles into living spaces.
Laboratory reports confirmed that the mined rocks, particularly dunite, contained high concentrations of silica, a substance long known to damage the lungs when inhaled chronically.
What villagers experienced daily now had a scientific explanation.
When Exposure Becomes Disease
Chronic bronchitis does not develop overnight. It is the result of years of continuous airway irritation, leading to inflammation, mucus hypersecretion, and irreversible structural changes in the lungs.
In Karya, exposure extended far beyond mine workers. Dust settled on homes, mixed with cooking smoke indoors, contaminated canals connected to the Kapila River, and coated agricultural land. The exposure pathways were multiple and cumulative:
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Airborne silica dust from mining and crushing
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Wind-assisted transport from elevated waste dumps
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Water contamination through runoff
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Long-term exposure spanning decades
Together, these factors created an environment highly conducive to chronic respiratory disease.
The Coldspot: Alatthuru as a Natural Contrast
Alatthuru village told a different story. Dense vegetation, absence of mining or industrial activity within a three-kilometer radius, predominantly agricultural livelihoods, and lower smoking prevalence created a protective environmental context.
Vegetation likely acted as a natural dust barrier, while the lack of industrial emissions minimized respiratory irritants. The absence of chronic bronchitis here was not accidental, it reflected a cleaner, less hazardous environment.
From One Village to a Broader Public Health Lesson
What began as unexplained suffering in a single village evolved into a powerful demonstration of how environmental determinants silently shape chronic disease. By integrating epidemiology with geospatial science, the study revealed risks that questionnaires alone could never uncover.
Chronic bronchitis, this study shows, is not merely a consequence of personal habits like smoking or cooking fuel use. It is also the outcome of where people live, what surrounds them, and what the wind carries into their lungs.
Karya’s story is not unique. Across rural India, many villages may be breathing the same invisible dust, unmeasured, unregulated, and unnoticed.
Geospatial science gave this village a voice.
Reference
Manjunatha, M. C., Madhu, B., Rekha, S., Murthy, N. V., Veeresh, S. J., Smitha, M. C., ... & Maheshwar, S. (2025). Evaluation of landfill sites as per Mysuru-Nanjangud Master Plan (2031) using weighted overlay method in GIS platform. International Journal of Geoinformatics, 21(8), 53-66.
This study transforms chronic bronchitis from an abstract statistic into a place-based public health reality. It demonstrates that protecting respiratory health requires not only medical treatment, but also environmental regulation, occupational safety, and spatial planning.
In understanding why one village could no longer breathe, this study offers lessons that extend far beyond its borders.
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