Match the following concrete example to the correct sequence of chain-of-infection steps: A COVID-infected person in a household sneezes; virus-laden droplets land on a doorknob; a roommate touches the doorknob and rubs their eye and later becomes colonized in the nasal mucosa. Which ordered sequence fits this scenario?

Which explanation correctly distinguishes droplet transmission from true airborne (aerosol) transmission?

An outbreak investigation finds identical bacterial strains from patient hand swabs and multiple shared workstation keyboards, but air sampling is negative for the organism. From an analytic standpoint, which mode of transmission is most likely driving the outbreak and which intervention should be prioritized?

Given an R₀ of 2.5 for a pathogen transmitted predominantly by short-range aerosols, calculate the effective reproductive number (R_e) after implementing an intervention estimated to reduce transmission probability by 60%.

Design a prioritized intervention package for an outbreak of a zoonotic bacterial pathogen maintained in feral rodents that occasionally spills into farm workers. Which combined set of actions best addresses both reservoir control and human protection?