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immunity –n. the ability to keep from being infected by a disease
contagious –adj. able to spread from person to person easily
fleeting –adj. lasting only a short time
swab –n. materials used to collect something from the body for medical tests
diagnose –v. to recognize a disease or illness in someone through medial methods
symptom –n. a change in the body that shows that a disease is present
encouraging –adj. giving hope that things will get better
