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dose – n. the amount of a medicine or treatment needed to treat a disease
income –n. money that is earned from work
surge –n. a fast increase in something
variant –n. something different in some way from others of the same kind
gene sequencing –n. a process that studies the order of DNA molecules to find out if organisms are related and to what extent
surveillance –n. to watch something very closely, especially to look for evidence of crime or disease
herd immunity –n. when enough people in a population can no longer be infected with a virus thereby protecting the rest of the people who are not immune from it
