Patrick Clay, a visiting grad student from Rice who will return as a postdoc this spring, is lead author on two papers exploring how interactions between parasites influence ecological dynamics. Most studies focus on just a single parasite infecting a host, but the norm in nature is that there are multiple parasites circulating in a population at a time. (If you doubt this, just visit the nearest daycare.)
In a Clay et al. paper that just appeared in The American Naturalist, we show that the order in which two parasites arrive in a single infected host influences the effects they have on each other and on the host. That, in turn, influences how likely it is that the two parasites will coexist. This paper uses data collected by former Duffy Lab undergrad Kailash Dhir.
The second paper (in press at Oikos) is a theory paper that shows that parasites that harm each other within individual hosts can actually facilitate each other’s spread at the population scale. These results suggest that within‐host priority effects can change host population‐scale infection patterns in systematic (and initially counterintuitive) ways, and that taking them into account may improve disease forecasting in coinfected populations.