The illustration for this learn node is from a Tufts University on “Emerging Infections and Agents of Biological Warfare.” The West Nile Virus transmission cycle is also illustrated in a chart at the Centers for Disease Control and Prevention (CDC). An interesting angle on the transmission is that protecting biodiversity of birds slows it down, as described in a Public Library of Science article:
We found there is lower incidence of human WNV in eastern US counties that have greater avian (viral host) diversity. This pattern exists when examining diversity-disease relationships both before WNV reached the US (in 1998) and once the epidemic was underway (in 2002). The robust disease-diversity relationships confirm that the dilution effect can be observed in another emerging infectious disease and illustrate an important ecosystem service provided by biodiversity, further supporting the growing view that protecting biodiversity should be considered in public health and safety plans.
