University of Helsinki
A group of researchers in the Università di Torino, Italy wanted to study how diseases spread among animal populations consisting of a predator species and a prey species. While this isn’t nearly the same as looking at the human population with more than 8 billion people, it helps us understand the process better and there could always be some method that could be extrapolated to our situation.
By looking into two different models of these populations, the researchers were able to find surprisingly different results for certain populations and in some cases some quirky characteristics of these disease spreads. For example, by looking at how some predators herd prey, like wolves and sheep, the researchers were able to find that only the sheep in the outside of the herd were attacked by wolves and thus, the disease transmits directly to wolves only by those sheep. Surprisingly, instead of wiping out either of the populations, the disease reaches a sort of equilibrium, affecting both populations but never taking over either of them.
Another example shows that when the prey live naturally longer lives, the disease spreads more within the population while not affecting much of the predators. Looking at the results of the research we can see that whenever a disease is present in an ecosystem such as the one studied here, while some characteristic populations will react differently than others, they will most often approach an equilibrium between the natural lifespan and the disease.
This research helps us notice that we should study this relationship further, as the difference in time it takes for an ecosystem to reach this equilibrium is important to us to better control diseases spread amongst for example farm animals. By changing how these animals live we could be better fit to react whenever a new disease shows up, which will decrease the amount of people affected by it and could even show us how to completely isolate the disease before it begins to exponentially spread.
Sources:
Venturino E. Disease Spread among Hunted and Retaliating Herding Prey. Mathematics. 2022; 10(23):4397. https://doi.org/10.3390/math1023439
Camilo – I never would have imagined that studying how diseases spread in animal populations could have relevance to human pandemics, but clearly we have a lot to learn from non-human organisms!
-Edie