If the disease is communicable, it is contagious. If it is airborne, it is transferred through the air, as opposed to physical touch or blood-borne. Being in a confined space, such as an ambulance, with an airborne communicable disease means you have most definitely been exposed to it.
Gathering information and data, since it refers to the key word: <em>timeline</em>.
Dilution is a term for thinning
