Complexity scientists present 'meme' model for multiple diseases

Once this shift occurs, microscopic changes in the transmission rate trigger macroscopic jumps in the expected epidemic size -- a spreading pattern that social scientists have observed in the adoption of innovative technologies, slang, and other contagious social behaviors.

STAR WARS AND SNEEZING

The researchers first began to compare biological contagions and social contagions in 2015 at the Santa Fe Institute, a transdisciplinary research center where Hébert-Dufresne was modeling how social trends propagate through reinforcement.

According to the researchers' model, the same super-exponential pattern characterizes the spread of social trends, like viral videos, which are widely shared and then cease to be relevant after a critical mass of people have viewed them.

DENGUE AND ANTIVAXXERS

A second important finding is that the same complex patterns that arise for interacting diseases also arise when a biological contagion interacts with a social contagion, as in the example of a virus spreading in conjunction with an anti-vaccination campaign.

It's a classic example of real-world complexity, where unintended consequences emerge from many interacting phenomena.

Although it is fascinating to observe a universal spreading pattern across complex social and biological systems, Hébert-Dufresne notes that it also presents a unique challenge.

"Looking at the data alone, we could observe this complex pattern and not know whether a deadly epidemic was being reinforced by a virus, or by a social phenomenon, or some combination."

"We hope this will open the door for more exciting models that capture the dynamics of multiple contagions," he says.