  We employ an agent-based contact network model to study the relationship
between vaccine uptake and disease dynamics in a hypothetical country town from
New South Wales, Australia, undergoing a COVID-19 epidemic, over a period of
three years. We model the contact network in this hypothetical township of N =
10000 people as a scale-free network, and simulate the spread of COVID-19 and
vaccination program using disease and vaccination uptake parameters typically
observed in such a NSW town. We simulate the spread of the ancestral variant of
COVID-19 in this town, and study the disease dynamics while the town maintains
limited but non-negligible contact with the rest of the country which is
assumed to be undergoing a severe COVID-19 epidemic. We also simulate a maximum
three doses of Pfizer Comirnaty vaccine being administered in this town, with
limited vaccine supply at first which gradually increases, and analyse how the
vaccination uptake affects the disease dynamics in this town, which is captured
using an extended compartmental model with epidemic parameters typical for a
COVID-19 epidemic in Australia. Our results show that, in such a township,
three vaccination doses are sufficient to contain but not eradicate COVID-19,
and the disease essentially becomes endemic. We also show that the average
degree of infected nodes (the average number of contacts for infected people)
predicts the proportion of infected people. Therefore, if the hubs (people with
a relatively high number of contacts) are disproportionately infected, this
indicates an oncoming peak of the infection, though the lag time thereof
depends on the maximum number of vaccines administered to the populace.
Overall, our analysis provides interesting insights in understanding the
interplay between network topology, vaccination levels, and COVID-19 disease
dynamics in a typical remote NSW country town.
