Michael Irvine

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  Heterogeneities in vector-bite exposure and infection distributions: implications for the elimination of lymphatic filariasis
  Michael Irvine

  Vector biting heterogeneity is believed to be strongly associated with the risk of vector-borne infectious diseases. Understanding the origins of heterogeneity in exposure and risk is important in both control and elimination. Two forms of heterogeneity can characterize the epidemiology of a disease: spatial and individual. These concepts are investigated within the context of lymphatic filariasis (LF), a parasitic, vector-borne disease that has been targeted for elimination.

  
  

  Infection and mosquito bite data for five villages in Papua New Guinea were used to understand these relationships before and after the introduction of bed-nets. We combine village-based analysis with geospatial modelling to quantify both individual and spatial heterogeneity. The introduction of bed-nets increased biting heterogeneity, but the reduction in mean biting more than compensated for this, by reducing prevalence closer to elimination thresholds. These results are then compared to an individual-based model of LF infection to estimate the impact of the number of years to reach elimination. We find that both spatial and individual heterogeneity are qualitatively different and can have profoundly different policy implications.