Researchers have found that drought may slightly increase the risk of diarrheal disease in children in the developing world, adding that wet areas are affected differently than dry areas.
Diarrhea is the second leading cause of death in children worldwide, and climate change is making droughts longer, more frequent and more severe, according to a new study published in the journal Nature Communications.
The study, based on data from 51 low- and middle-income countries, found that children were more likely to have diarrhea after recent drought conditions for six months to two years, although the effects of drought were dry, temperate and dry. The tropical climate was different. region.
Previous studies have found links between diarrheal disease and rainfall, floods and weather, but little was previously known about the effects of drought.
The new study “fills the void of understanding the effects of flooding, extreme rainfall and seasonal contrast specifically associated with drought,” said Joseph Eisenberg, an epidemiologist at the University of Michigan who was not involved in the study.
“Water plays an essential role in helping to address the problem as well as increasing the risk of being exposed,” he said.
Water needed for good hygiene
Water is central to the spread and prevention of diarrheal disease. The germs that cause diarrhea survive and spread in water, but water is also important for hygienic practices, such as hand washing, which prevent infection.
Study author Pin Wang, an environmental epidemiologist at Yale University, and his colleagues thought that drought may force families to prioritize scarce water for drinking rather than washing, leaving children more vulnerable to diarrhea. .
“Drought can directly affect WASH (water, sanitation and hygiene) practices,” Wang said. “Due to insufficient water supply, people may prefer water for other essential uses like drinking, but not for hand washing and flushing. [the] toilet.”
Wang and his colleagues combined weather records with data on diarrhea in more than 1.3 million children under the age of 5 from the Demographic and Health Survey Program, which used representative households in developing countries to collect data on health and demographics. conducts survey. Data from the Demographic and Health Survey also included information on each child, household assets and WASH practices.
Using this data, the researchers then determined whether the children in the dataset had experienced drought, how long the drought lasted, and how severe it was relative to normal conditions.
Correcting for differences between households and separated children, the researchers found that six months of drought exposure slightly increased the risk of diarrhea in children under the age of 5. The risk was 5% higher after mild drought and 8% higher after severe drought. The strength of the impact of drought on diarrhea depends on other factors such as local climate, sanitation and access to water.
In arid regions, a drought lasting six months did not significantly affect the rate of diarrhea, but a drought lasting two years did.
The authors speculate that this may be because these arid regions are already prepared for short periods of water scarcity, but cannot withstand very long droughts. On the other hand, tropical and temperate regions saw a worse impact in a six-month drought than a longer one, perhaps because they are less prepared for water loss in the short term but in general to help adapt in the long term. More water is available.
The researchers found that families in droughts washed their hands and performed other wash practices less frequently than those who were not experiencing drought. It is responsible for an increase in diarrhea rates by about 10% in mild droughts and about 20% in severe conditions.
Children whose families needed to walk for more than 30 minutes to collect water also had a higher risk of severe drought-associated diarrhea than children whose families had access to water.
more study needed
Eisenberg said the study was a good first step, but that more studies would be needed to confirm the results.
“I think the biggest implication … as a hypothesis-producing result is it would encourage and motivate people to do some more sophisticated studies to back up the findings.”
Wang also said that future studies would be needed to support his findings. And as climate change is expected to shake up rain patterns around the world, he said he hopes their result will translate into policy that will protect children from diarrheal disease caused by drought.
“We clearly think that with climate change, there will be a higher incidence of drought events in the future, especially in places that are already receiving less rainfall,” Wang said. “We need to reduce greenhouse gas emissions, that is the first thing. The second is that WASH variables should be emphasized or prioritized – especially in these low- and middle-income countries. The risk of diarrheal People need better WASH practices to do less.
