What is an antigen? Antigen refers to any foreign substance which on entering the body  stimulates the production of antibodies in the body of the  individual as a part of the immune response.
Gen Z Defined. Gen Z consumers range from ages 2 to 19, though the target range for marketers lies from ages 11 to 16. Gen Z is the most diverse and multicultural of any generation in the U.S. -- 55% are Caucasian, 24% are Hispanic, 14% are African-American and 4% are Asian. Gen Z Beliefs.
The Food and Drug Administration has approved the use of the varicella-zoster vaccine (Zostavax) for adults age 50 and older, whether they've already had shingles or not. Although the vaccine is approved for people age 50 and older, the Centers for Disease Control and Prevention isn't recommending it until you reach age 60 or older, when the risk of shingles and its complications is highest.