Pathogen - A biological agent that causes disease.⏎
Replication - The process of producing a copy of a strand of DNA.⏎
Outbreak - An unexpected increase in the incidence of a particular disease over a given time period and geographic range. A general term that may refer either to an epidemic or a pandemic.⏎
Reservoir - An organism in which a parasite that is pathogenic for some other organism lives and reproduces without harming its host.⏎
Peptic Ulcer - An open sore that develops on the inner lining of the stomach or upper small intestine.⏎