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pandemic – n. occurrence of disease that spreads very quickly and affects a large number of people over a wide area or throughout the world
contagious – adj. able to be passed from one person or animal to another by touching
symptom – n. a physical feeling or problem that indicates a person has a particular illness
cough – n. physical condition or illness that causes someone to cough
avian – adj. of or relating to birds
peak – v. to reach the highest level
