Bangladesh Floods Case Study

Case study of a country which has experienced a natural hazard and the implications this has had on a named disease

Geological area covered by hazard and its influence on risk and outbreak of disease

• Deltaic country inevitably prone to significant annual river floods

• Floods support largely rural population (2019: >60%) by delivering 1 billion tonnes of fertile soil.

• 3 major rivers: Ganges, Brahmaputra and Meghan - all rise in the Himalayas.

• 80% land area of country benefits from flooding.

Environmental factors affecting spread of disease

• Annual floods due to rivers and impact of monsoon season.

• Exposure to flooding increasing as climate change exacerbates flood risk (ST) + regional subsistence from plate tectonics makes country more liable to river and coastal flooding.

• Frequency of high magnitude floods increasing: since 2015, 6 consecutive years of high magnitude floods.

Human factors affecting spread of disease

• Large rural populations (60%) as flooding creates soil for farming: vital agricultural resource.

• High pop. densities up to 1000 people per km2 - artificial surfaces, reduced drainage.

Disease in Bangladesh

• Transmission of water-borne pathogens increases during flood years.

• 2020 floods triggered diarrhoea epidemic and typhoid + hepatitis as drinking water and food became contaminated by bacteria present in floodwaters.

• In a year dominated by COVID-19 pandemic, separating the impact of one of the largest and longest floods in country's history and impact of pandemic was very difficult.

• First two months of the floods: over 40% of country was flooded.

Impacts of disease on resident populations 2020 floods

• 3.3 million people affected

• 750,000 homes waterlogged

• 110,000 hectares of crops destroyed

• 2000 schools destroyed

• 80 people died

• 4500 became ill due to contaminated water

Strategies to minimise impacts at different scales

• Particularly serious for young children: globally 1 child under 5 dies every 2 minutes as a result

• Solution is to provide clean water and efficient sanitation (significant economic challenge in poorer countries)

• Despite floods, Bangladesh has had some success in reducing impact of diarrhoea - widely attributed to number of policies implemented by government and NGOs allowing swift intervention in flooded areas to support: o Use of oral rehydration solution (ORS) o Promotion of breastfeeding, reducing formula milk (preventing water borne diseases) o Encouraging handwashing and sanitary latrines o Use of water purification tablets o Improvements in female education and nutrition

• Policies saved up to 70,000 lives in 2015

• Along with marginal improvements in diet and access to medical support, this has been a major achievement for one of the world's most hazardous environments.