We may be able to more accurately identify regions of concern about the emergence and spread of Neglected Tropical Diseases by taking into account the physical, chemical, fertility, and microbiological features of soil health, says a study

Does climate change affect soil health in a manner that promotes the spread of neglected tropical diseases (NTDs)? 

The answer to this question is in the study by John Paul M. Wasan, a researcher at Department of Plant Sciences, University of Saskatchewan in Canada and Kishor M. Wasan, a Co-Director and Co-Founder, Neglected Global Diseases Initiative at The University of British Columbia.

In their latest article published in PLOS Neglected Tropical Diseases (PLOS NTDs), a peer-reviewed open access scientific journal dedicated to the study of NTDs, the authors say that understanding how climate change affects soil characteristics can help predict and manage the spread of NTDs. 

“This, in turn, can assist local public health experts in predicting and managing the spread of NTDs,” the authors state. “We also suggest that unlike unpredictable climatic factors, soil health can be directly managed through appropriate land use practices.”

The climate change, authors say, has led to a significant increase in temperature, precipitation, humidity, and the frequency and intensity of storms, thereby creating optimal conditions for the emergence and spread of vector-borne NTDs in previously unaffected regions. They caution the increased emergence of NTDs due to the worldwide spread of such vectors should not be underestimated. For instance, the tiger mosquito (Aedes albopictus) can transmit various arboviruses like dengue fever, yellow fever, West Nile virus, and nematode-borne parasitic diseases.

The authors propose that investigating relevant soil characteristics may enhance disease models, identify areas of concern, and suggest land management practices to mitigate the spread of NTDs. The “healthy” soils, which may hinder disease spread, can be improved and managed, similar to public health, the authors explain. 

According to the authors, soil health is generally defined in terms of ecosystem services (benefits of nature to humans), such as water retention, nutrient cycling, and supporting plant life. 

Physically healthy soils are well aerated and have balanced moisture content, they say adding the structure of a soil, the assembly of soil aggregates, greatly affects water movement and  drainage. 

“Improving soil structure through active land management (promoting root development to increase pore size) can aid in reducing standing water,” the authors point out. “Poor management, such as frequent soil compaction by machinery, can also degrade structure and impede water movement.”

They propose avoiding use of contaminated irrigation water or manure, as well as modifying irrigation methods to limit prolonged saturated conditions, may be strategies to reduce soil-based NTD risk. 

“By considering physical, chemical, fertility, and microbiological characteristics of soil health, we may be able to better identify areas of concern related to the development and spread of NTDs,” the study says. “Soil scientists, land managers, agronomists, farmers, and others are in a unique position to assist healthcare professionals in the fight against NTDs.”

Also read: Climate change debate: putting health first