Contact Only

Even though Cholera is importantly and necessarily environmental, we want to explore contact-only transmission behavior first

Single Node

We run for 5 years, seeding with a one-time initial outbreak of 0.25%. As long as the population is >~ 400,000, the outbreak seems to "take".

Below explore how this varies by population and birth rate.

10 Nodes Varying by Population

Population varies from 1e5 to 1e7. Low Birth Rate (10):

High CBR (40):

Multi-Node, NOT Spatial

25 independent nodes, varying by Initial Population and Birth Rate

S, I and Pop

SI Orbitals

Observations

• As population increases, we're more likely to reach endemicity
• As birth rate increases, we're get more susceptibles more often, we should be more likely to reach endemicity with smaller initial populations?
• For any scenario in which endemicity is achieved, the curve and prevalence (as a fraction) are the same even as population and birth rates increase (??)

Environmental Transmission

Now let's add environmental transmission. We won't review all the details of this additional route. The main feature is that contagion is shed into the environment and as a result doesn't decay away to nothing each timestep, but rather persists for some time.

S, I and Pop

Outbreak removed.

Sparklines! (Demonstrates seasonal outbreaks)

SI Orbitals

This plot compares contact-only, environmental-only, and combined transmission. It keeps y axis extents common across all plots.