Planning for climate change: The need for mechanistic systems-based approaches to study climate change impacts on diarrheal diseases

Abstract

Increased precipitation and temperature variability as well as extreme events related to climate change are predicted to affect the availability and quality of water globally. Already heavily burdened with diarrheal diseases due to poor access to water, sanitation and hygiene facilities, communities throughout the developing world lack the adaptive capacity to sufficiently respond to the additional adversity caused by climate change. Studies suggest that diarrhea rates are positively correlated with increased temperature, and show a complex relationship with precipitation. Although climate change will likely increase rates of diarrheal diseases on average, there is a poor mechanistic understanding of the underlying disease transmission processes and substantial uncertainty surrounding current estimates. This makes it difficult to recommend appropriate adaptation strategies. We review the relevant climate-related mechanisms behind transmission of diarrheal disease pathogens and argue that systems-based mechanistic approaches incorporating human, engineered and environmental components are urgently needed. We then review successful systems-based approaches used in other environmental health fields and detail one modeling framework to predict climate change impacts on diarrheal diseases and design adaptation strategies.

El Niño Southern Oscillation (ENSO) and Health: An Overview for Climate and Health Researchers

“…Notwithstanding the complex pathways linking climate anomalies and diarrhoea [69] and the challenges this poses for quantifying the effects of weather and climate on water-associated diseases in general [70][71][72], diarrhoeal illness is generally sensitive to climate anomalies [73][74][75][76][77][78] with unusually warm conditions conducive to enhanced pathogen replication and survival rates, while rainfall surpluses may transport faecal matter into water courses with micro-organisms becoming concentrated in water bodies during periods of rainfall deficit. While Demisse and Mengisitie [79] noted that El Niño has an impact on diarrhoea incidence for a number of major geographic regions, many of the cited papers address temperature/rainfall-diarrhoea association as opposed to climate driven variations in diarrhoea moderated by ENSO.…”

Introduction to the Importance of Sanitation

“…water, energy, nutrients, and chemicals) but still prevents exposure to pathogens over the complete sanitation chain. Provision of basic sanitation may also protect people from adverse health effects associated with outcomes of climate change such as increases in temperature and rainfall intensity Mellor et al, 2016 borehole, a protected spring, and rainwater collection systems). Examples of unimproved sources are: tank truck, or bottled water and unprotected wells and springs.…”

Virulence factor activity relationships (VFARs): a bioinformatics perspective

“…106 At the community level, factors to consider may include access to clean drinking water and resources for mitigation. Communities with a lower income may be at a greater risk to emergence and transmission.…”