The Impact of El Niño on Diarrheal Disease Incidence: A Systematic Review

Abstract

Climate change is becoming a huge threat to the health especially for those from developing countries. Diarrhea is one of the major diseases linked with changing climate. Global climate change is expected to increase the risk of diarrheal diseases, a leading cause of childhood mortality. El Niño Southern Oscillation (ENSO) is a climate event that originates in the Pacific Ocean but has wide-ranging consequences for weather around the world, and is especially associated with droughts and floods. An El Niño occurs approximately every 3 to 7 years when warm equatorial water shifts from Western to Eastern Pacific ocean. However, there is uncertainty about the impact of climate change/ESNO on the transmission of diarrheal pathogens and diarrhea disease. The aim of this systematical review is to examine the impact of El Niño on diarrheal disease incidence in children and adults. An extensive literature review was conducted in January 2017 using electronic databases Google Scholar, PubMed, and Directory of Open Access Journals (DOAJ). The review was limited to studies reporting the impacts of El Niño on diarrheal diseases or studying associations between climate change associated with El Niño and diarrheal diseases outcomes. Over 2600 scholarly papers and potential published articles identified in the initial electronic search, of which 30 fulfilled the inclusion criteria. Evidence for an association between disease risk and ENSO is more robust when analyses use a long time-series that incorporate more than one event and when there is an appropriate geographical aggregation of data. On the basis of the evidence available, this review primarily draws upon observational studies. The result of this systematic review confirmed that most of the studies noted a significant association between diarrheal disease and El Niño. However, research on the impact of El Nino/climate change on diarrhoeal disease is limited. Longitudinal studies over extended periods of time that investigate the link between El Nino/climate change and diarrheal disease are needed. There is a need for studies to be expanded to include more countries in the region and to include other environmental, social and economic factors that might affect the incidence of diarrheal disease.

Pathogen-Specific Impacts of the 2011–2012 La Niña-Associated Floods on Enteric Infections in the MAL-ED Peru Cohort: A Comparative Interrupted Time Series Analysis

“…In order for health systems to adapt to mitigate the impacts of climate change, evidence is needed of the impacts of extreme weather events on specific outcomes of public health importance. The El Niño-Southern Oscillation (ENSO) phenomenon is a cause of both flooding and droughts across multiple continents and has been shown to be associated with increases in childhood diarrhea in Peru, the United States and elsewhere [43][44][45]. Climate change may increase the frequency of ENSO events as well as the global land area that is subject to its precipitation impacts [46,47].…”

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

“…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.…”

Can El Niño–Southern Oscillation Increase Respiratory Infectious Diseases in China? An Empirical Study of 31 Provinces

“…Meteorologically, the warmer period of the ENSO is often called El Niño, and the colder period is called La Niña [ 14 ]. Furthermore, ENSO has been proven to impact the morbidity of infectious diseases, such as dengue fever, diarrhea, and malaria [ 15 , 16 , 17 ]. For example, Xiao et al [ 16 ] found that El Niño may have contributed to the dengue fever epidemic from 1995 to 2010 in Guangdong, China.…”