The links between increasing rates of infectious disease emergence (e.g., Zika virus, Ebola virus, Lyme disease) and recent erosion of biodiversity have attracted much recent attention, and also controversy. Often, studies fail to address the spatial and temporal disconnect between aggregated ecological data and the host-pathogen interaction that results in disease transmisison e.g., host behaviors.
We have conducted surveillance of tick-borne diseases - Lyme disease, and the newly recognized Borrelia miyamotoi - in protected areas of California. We have also initiated a citizen science project to facilitate data collection on how and when people are exposed to tick-borne diseases. We approach the health issue of (emerging) tick-borne disease simultaneously using these two data sources.
We demonstrate the dangers of using aggregate data to understand emerging zoonotic diseases, which can lead to the conclusion that the Lyme disease epidemic in the US could be prevented by a fried chicken diet. In contrast, we show that marrying ecological and epidemiologic approaches and scales results in more pertinent insights. For example, ecological surveys suggest that human exposure should be highest in December-January, yet citizen-submitted samples suggest that actual exposure peaks in early Spring. Human exposure to ticks occurs predominantly during outdoor recreation, but exposure to tick-borne disease (Borrelia) is proportionally greater in the peri-domestic environment. In California, the Lyme disease bacterium is displaced by Borrelia miyamotoi along a north-to-south gradient, which we attribute to a shift in the ecology of reservoir hosts. This research highlights the usefulness of an integrated 'One Health' approach to understanding the local context of emerging zoonotic diseases.