  Besides mimicking bio-chemical and multi-scale communication mechanisms,
molecular communication forms a theoretical framework for virus infection
processes. Towards this goal, aerosol and droplet transmission has recently
been modeled as a multiuser scenario. In this letter, the "infection
performance" is evaluated by means of a mutual information analysis, and by an
even simpler probabilistic performance measure which is closely related to
absorbed viruses. The so-called infection rate depends on the distribution of
the channel input events as well as on the transition probabilities between
channel input and output events. The infection rate is investigated
analytically for five basic discrete memoryless channel models. Numerical
results for the transition probabilities are obtained by Monte Carlo
simulations for pathogen-laden particle transmission in four typical indoor
environments: two-person office, corridor, classroom, and bus. Particle
transfer contributed significantly to infectious diseases like SARS-CoV-2 and
influenza.
