An Epidemic Model for Bats
Bats are reservoirs of coronaviruses (viruses that shut down our immune response). In fact, bats co-exist with over 200 different viruses, the most of any mammal (even rodents), and exhibit no signs of disease. Sometimes, these coronaviruses jump species, from bats to humans, and wreak havoc on our population since we are not nearly as suited to handle them. Bats have existed for generations alongside these viruses, and have essentially developed an evolutionary equilibrium with them.
The issue occurs when any of these viruses jump from the bats to another species. The virus SARS-CoV infected over 8,000 peoples worldwide after jumping onto us from a bat population. In humans, this can be clearly shown by a SIS epidemic model with a very high probability of passing the disease. Human’s immunes systems are much, much weaker compared to bat’s and an epidemic is even more clearly modeled by a regular branch diagram, with R0 far greater than 1.
The interesting question is whether introducing a new viral epidemic into the bat population will either be shut down immediately or spread into the entire population. Looking at a branching model, it is very likely that due to the bat’s outstanding immune system, we can infer the virus spreads with probability close to 0, and the virus will die out within a few levels of the tree. However, the bat’s also are capable of co-existing with the virus and hosting them instead. This could possibly be well represented by a SIR model, where the R (Removed) state actually means the bat might no longer be contagious, but will still host the virus. While there are many possible ways to model the bat population’s epidemics, overall they will most likely stay healthy with their biological immunity to viruses, while humans could be annihilated quickly.
http://theconversation.com/can-bats-help-humans-survive-the-next-pandemic-85799