Climate change to drive increased hospitalizations from diarrheal diseases in Dhaka

By 2100, hospitalizations from diarrheal diseases are predicted to increase in the city of Dhaka in Bangladesh as a result of climate change, even if global warming stays under 2 degrees Celsius. Farhana Haque and colleagues from University College London, London School of Hygiene and Tropical Medicine and icddr,b report these findings in a new study published September 26 in the open access journal PLOS Neglected Tropical Diseases.

As one of the world's most densely population cities, Dhaka deals with a high burden of diarrheal diseases. While some studies have looked at how weather affects diarrhea in Bangladesh, few have examined the future impact of climate change. A warmer climate is expected to worsen this public health issue by making the city hotter and exacerbating water quality issues.

In the new study, researchers estimated the risks posed by diarrheal diseases under various global warming scenarios. They looked to see if daily rainfall, humidity and temperature in Dhaka affected rates of hospitalizations from diarrheal disease, using data from about 3 million diarrhea cases treated at a major hospital in Dhaka from 1981 to 2010. Statistical analysis revealed that higher daily temperatures significantly increased the risk of diarrhea for all age groups. Assuming that the planet warms by 1.5 °C to 2 °C on average, hospitalizations due to diarrheal disease are expected to increase by 4.5% to 7.4% in all age groups by the end of the century. Children under five may be especially hard hit, with hospitalization rates estimated to increase by 5.7% to 9.4%.

Under the Paris Agreement, an international treaty on climate change, countries agreed to set global warming targets to under 2°C. The new study shows that even if these targets are met, hospitalizations from diarrhea will increase substantially in Dhaka. These findings underscore the importance of better preparing the city to prevent and manage diarrheal diseases.

The authors add: "Diarrhea hospitalization will increase significantly in Dhaka by 4.5 – 7.4% in all age groups by the 2100s even if the global warming targets adopted by the Paris Agreement is reached. This underscores the importance of preparing the city for management and prevention of diarrheal diseases."