Getting Too Old for This: The connection between age and disease spread

By Meg Thode

            Researchers from the University of Edinburgh’s School of Biological Sciences have found a connection between age distribution and disease spread in animals. Using computer modeling and lab experiments with water fleas (small, marine crustaceans) they simulated outbreaks of bacterial infections among populations with different demographics. They found the age at time of exposure, as well as the age at which females become mothers, are most significant for determining the rate of disease spread (with younger populations being more vulnerable). Unexpectedly, they found that high death rates can cause a disease to spread even faster. This contradicts the usual expectation that a high death rate would slow the progression of an epidemic as the population becomes less dense.

The team hopes to further develop its mathematical model of how the spread of disease affects organisms and populations long-term. The study leader, Jess Clark, frames it in the modern demographic transition: "Many societies around the world are experiencing aging populations, and investigating the impact of this might lend valuable insight into how such populations might respond to an outbreak of disease."


University of Edinburgh. (2017, March 24). Spread of ages is key to impact of disease, animal study finds. ScienceDaily. Retrieved March 29, 2017 from