Q: My 9-month-old child was given the measles vaccine yesterday. The doctor told me that the child will develop fever. But till now the child has not developed fever. Does this mean that the vaccine is not effective? What is the course of action?

A:Fever and transient rash develops in only 5-15 per cent of the recipients of the measles vaccine. Amongst them, the reactions begin 5 to 12 days after the vaccination and usually lasts for a few days. Thus the absence of fever on the second day of vaccination does not mean that the vaccine is ineffective. There is no need for you to do anything.