Question

At what age is the first dose of measles vaccination given?

• A. 9 months
• B. At birth
• C. 4 weeks
• D. 8 weeks

Hint:

Wait until maternal antibodies decline but before natural measles strikes.

Answer 1

The Correct Option is A

Step 1: Decide the age by balancing two facts: a young infant carries protective antibodies from the mother, and those same antibodies interfere with a live vaccine.

Step 2: Give the vaccine too soon and maternal antibody knocks out the vaccine virus before immunity forms. Wait too long and the child may catch wild measles first. The compromise point, where maternal antibody has declined yet risk is still high, is around 9 months.

Step 3: That is exactly the age the WHO immunization programme picks for the first measles dose, with a follow-up dose between 16 and 24 months in the Indian schedule to catch non-responders.

Step 4: Birth, 4 weeks, and 8 weeks are all inside the maternal-antibody window, so they are unsuitable. The correct first-dose age stands at 9 months.

\[\boxed{\text{9 months}}\]