Which of the following is a common contraindication to vaccination?

• A. Mild fever or illness
• B. Severe allergic reaction to a previous vaccine component
• C. Being a healthcare worker
• D. Vaccination in pregnancy for all vaccines

Answer: (B)

A severe allergic reaction to a previous vaccine component is a contraindication because it signals a high risk of an immediate, potentially life-threatening reaction if the same vaccine or its components are given again. If someone has had an anaphylactic or similarly severe allergy to something in a vaccine, exposing them to that component again could trigger another reaction. To protect safety, that specific vaccine is avoided or given only under special precautions.

Mild fever or illness is not a contraindication in most cases; you can often vaccinate unless the illness is moderate to severe. Being a healthcare worker isn’t a contraindication by itself; vaccination decisions aren’t based on occupation. And pregnancy isn’t a blanket contraindication for all vaccines—many vaccines are safe and recommended during pregnancy (though some live vaccines are avoided).