Paul Hynds (Ireland)
Technological University Dublin Environmental Health InstitutePresenter of 1 Presentation
PROGRESSION FROM VTEC ENTERITIS TO HAEMOLYTIC URAEMIC SYNDROME (HUS) AMONG PAEDIATRIC CASES IN THE REPUBLIC OF IRELAND: A RETROSPECTIVE CASE/CASE STUDY (ID 147)
Abstract
Background
Ireland currently has the highest VTEC notification rate in Europe, progressing to haemolytic uraemic syndrome (HUS) in approximately 5-10% of cases and most frequently among paediatric cases. To date the effect of “place” as it relates to VTEC serotype, source, pathway and receptor have received little attention.
Methods
All confirmed cases of paediatric (≤ 5 years ) VTEC enteritis notified from January 1st 2013 to December 31st 2017 were geo-coded to one of ~19,000 Census Small Areas, and binary coded (Y/N) for HUS progression. Several national datasets were geo-referenced to the case dataset including socioeconomic profile, hydrogeological setting, landuse, and infrastructure , with penalised classification models employed to account for statistical “rarity”. Chi-square Automatic Interaction Detector (CHAID) trees were used to identifyattribute “breakpoints” .
Results
Overall, 63 cases of paediatric HUS (63/1,102; 5.7%) were analysed, with a classification accuracy of approximately 96% (60% of HUS cases accurately classified). Case age (breakpoint ≤3 years), case type (hospital inpatient), and VTEC serotype (O157, O26) were significantly predictive. Socioeconomic components (female unemployment rate ≤13%, rented accommodation >20%) and groundwater vulnerability classification (breakpoint: high/extreme) were also predictive. Local spatial attributes (deprivation, groundwater) were more significant than regional variables.
Conclusions
Developed models could be used as an “early-warning” system for HUS progression among paediatric VTEC cases. While VTEC progression appears to be both case- and therapy-related (i.e., severity), there is also a level of spatiotemporality. The association with groundwater vulnerability indicates a waterborne mode of transmission, with elevated groundwater vulnerability in parallel with higher rates of progression potentially due to higher VTEC contamination rates (i.e., dose). Higher levels of affluence associated with HUS progression may potentially serve as a proxy for exposure i.e. international travel, dietary variation and/or healthcare access.