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outbreak – n. a sudden rise in the number of cases of a disease
dose – n. the amount of a medicine, drug, or vitamin that is taken at one time
mosquito – n. a small flying insect that bites the skin of people and animals and sucks their blood
transmit – v. to infect someone else with a virus or disease
defect – n. a physical problem; something that causes weakness; a lack of something needed for something to operate perfectly
mutation – n. a change in the genes of a plant or animal that causes physical characteristics that are different from what is normal
