The reason why it is harder to determine exposure is because Bloodborne transmitted diseases need a physical medium to be transfered. It can be easily traced back to its sources and be measured, calculated, contained and treated. However, airborne transmitted diseases lack this feature. The microorganism do not need a physical medium to transfer from one host to another so the exposure is harder to control and contain.
Because with bloodborne transmitted diseases there is actual physical contact, whereas with airborne transmitted diseases, it takes a while for contact to be made. Hope this helps.
Edgar uses a variety of literary devices in his diction. He uses irony in "The Cask of Amontillado". The irony that Poe employs foreshadows the imminent death of Fortunato.
