Diarrheal Disease in Northwestern Ecuador: Prevalence, Pathogenicity, and Transmission of Enteric Pathogens Accross the Region.

Diarrheal Disease;Enteric Pathogen;Rotavirus;Rainfall;Water;Sanitation;Public Health;Health Sciences;Epidemiological Science

Bhavnani, DarleneWilson, Mark L. ;

University of Michigan

关键词: Diarrheal Disease;    Enteric Pathogen;    Rotavirus;    Rainfall;    Water;    Sanitation;    Public Health;    Health Sciences;    Epidemiological Science;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/91604/dbhavnan_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Over four billion episodes of diarrhea occur worldwide each year. The burden of diarrhea is particularly high for children under five years living in developing countries. One in five child-deaths are attributed to diarrhea making it the second leading cause of child-mortality. Motivated by the large diarrheal disease burden, this body of research seeks to better understand the causes of diarrhea in developing country settings. We focus our research on diarrhea in northwestern Ecuador, a remote and underdeveloped region with limited access to health care and poor sanitation infrastructure. In chapter two, we estimate the prevalence and pathogenicity of three marker pathogens circulating in the region; rotavirus, Giardia and Escherichia coli (E. coli). We take this up further by addressing the effects of coinfections on diarrhea. Our main finding is evidence for synergistic interactions between rotavirus and coinfecting pathogens, such that the pathogenic potential of each organism may be enhanced. In chapter three, we identify and characterize a regional epidemic of one of these pathogens, enteroinvasive E. coli (EIEC). We show that EIEC swept through northwestern Ecuador causing a prolonged epidemic that lasted nearly 3 years. The epidemic involved at least six communities and 31 unique genotypes. Based on spatial and temporal data we suggest that a centrally located community, Borbón, may have played a key role in sustaining these infections while they spread to surrounding communities. Changing the focus from transmission between communities to transmission within a community, we shift our attention to Borbón. In chapter four, we highlight the importance of environmental context such as extreme rainfall events on the effectiveness of diarrhea interventions. We show that the protective effects of improved sanitation facilities decrease after heavy rainfall. In contrast, the protection offered by safe water sources increase after heavy rainfall. These results suggest a ;;flushing effect”, where during heavy rainfall, pathogens in the environment are flushed out of contaminated latrines and flushed into unsafe water sources, such as uncovered wells and rivers. This body of research highlights the importance of both biological and environmental interventions for diarrhea.