VOA慢速英语:Highly Contagious Virus Sickens Millions, Costs Billions

rare – adj. seldom occurring or found

intestinal – adj. affecting, occurring, or living in the intestine : of, relating to, or being the intestine

quantify – v. to find or calculate the quantity or amount of (something)

characterize – v. to describe the character or special qualities of (someone or something)

impact – n. to have a strong and often bad effect on (something or someone)

widespread – adj. common over a wide area or among many people

obligated – v. to make (a person or organization) do something because the law requires it or because it is the right thing to do

contaminate – v. to make (something) dangerous, dirty, or impure by adding something harmful or undesirable to it