One of the leading causes of child death in South Asia and Africa is preventable diarrhea. In developing countries, the severe lack of access to sanitation, clean water and healthcare facilities makes preventing and limiting the spread of infectious diseases even more challenging. According to a recent study published in the journal Proceedings of the National Academy of Sciencesincreased frequency of droughts and heavy rainfall is associated with increased rates of diarrhea among children under 3 years of age.
“Climatic conditions are becoming more and more suitable for the transmission of various waterborne and vector-borne diseases. At the same time, the increased incidence of extreme weather events attributed to climate change has been shown to amplify disease transmission channels, such as the accumulation of pathogens in scarce water supplies and contact with contaminated water after floods, the researchers wrote in their study.
The climate crisis is destabilizing and changing the global water cycle – exacerbating the phenomenon known as ‘dry gets drier, wet gets wetter’. Non-seasonal heavy rains during the dry season can cause a sudden and drastic increase in the concentration of pathogens entering water sources.
To further investigate the link between rainfall shocks such as droughts and floods and diarrhea in children, researchers analyzed survey data from an international development group that included 611,154 children under the age of 3 from 51 countries between 2000 and 2019. The children’s families were interviewed to determine when and how they began experiencing diarrhea symptoms.
Anna Dimitrova, a researcher at the Scripps Institution of Oceanography at the University of California, San Diego, and colleagues then correlated the survey data with climate data. They observed that children from the tropical savannah and humid subtropical zones reported the highest prevalence, 18.5% and 18.3%, respectively. The lowest incidence of diarrhea (16.6%) was recorded among children in the humid subtropical zone.
Drafts have been associated with an increased risk of diarrhea in tropical savannah regions, and in humid subtropical regions, heavy rainfall has been associated with a higher incidence of diarrhea.
Researchers have highlighted that certain interventions can significantly reduce the risk of diarrheal disease among children. This includes the safe disposal of children’s stools, rotavirus vaccination, hygienic eating practices, and water treatment before consumption.
“Our results suggest that interventions should be aimed at improving education about water treatment methods during heavy rainfall, particularly among households with access to residential water that may not be aware of water quality degradation,” the researchers note.
However, scientists also acknowledge that extreme weather events, such as floods, can repeatedly damage and destroy sanitary facilities and cause sewage overflows. While droughts prevent communities from regularly washing their hands and practicing other hygiene practices, thus increasing the risk of children developing diarrhea.
“Among other health risks, malnutrition in childhood increases susceptibility to diarrheal diseases and is the leading cause of death in children. The results presented underscore the need to reach food-insecure households and to include minimum nutritional standards in food assistance programs targeting young children, the researchers concluded. “Improving knowledge about healthy eating practices can also be implemented at low cost in places where such practices are not widely followed.”