Which statement describes inactivated vaccines?

• A. They are stable and safer, but not as effective and require several doses and boosters
• B. They always provide lifelong immunity with a single dose
• C. They cannot be stored in the refrigerator
• D. They never require boosters

Answer: (A)

Inactivated vaccines are made from organisms that have been killed or inactivated, so they cannot cause disease. This makes them stable and generally safer with fewer strong side effects. Because they don’t replicate in the body, the immune response they provoke is typically weaker, so protection often isn’t as robust or long-lasting as with live vaccines. To achieve and maintain adequate immunity, several doses and boosters are usually needed.

They can be stored in standard refrigerator temperatures, which helps with distribution and shelf life. Because of the weaker immune response, a single dose does not usually provide lifelong immunity, and boosters are commonly required. This is why the statement that they are stable and safer but require several doses and boosters best describes inactivated vaccines.