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initially – adj. of or relating to the beginning
transmission – n. the act or process by which something is spread or passed from one person or thing to another
infect – v. to cause (someone or something) to become sick or affected by disease
vaccine – n. a substance that is usually injected into a person or animal to protect against a particular disease
continental US – n. the 48 states between Canada and Mexico; does not include Hawaii, Alaska or US territories such as Puerto Rico
Americas – n. the countries of North, Central and South America
dengue – n. a disease spread by mosquitoes that causes flu-like sympts. It can develop into severe dengue, which can be fatal.
condom – n. a thin rubber covering that a man wears on his penis during sex in order to prevent a woman from becoming pregnant or to prevent the spread of diseases
screen – n. a sheet that is made of very small wire or plastic strings which are woven together and that is set in a frame in a window, door, etc., to let air in but keep insects out
