Contraindications to vaccines: which statement is true?

• A. There are no contraindications to vaccines
• B. Live vaccines are contraindicated in pregnant women, immunocompromised, and infants
• C. There are risk-based contraindications but not universal rules
• D. Vaccines can always be given regardless of health status

Answer: (B)

Vaccination safety for those who may be harmed by a vaccine is the key idea. Live vaccines contain a weakened organism, which can still cause illness in people with certain vulnerabilities. In pregnant women, a live vaccine could affect the fetus, so they are generally advised not to receive these vaccines. In individuals who are immunocompromised, the weakened organism could cause a more serious infection because their immune system can’t control it. Likewise, very young infants have immature immune systems and are more susceptible to adverse effects from live vaccines. Because of these safety concerns, live vaccines are contraindicated in these groups, making that statement true.

There are clearly contraindications to vaccines, so saying there are none is incorrect. While many vaccines are given based on risk and timing, blanket statements that ignore these safety considerations aren’t valid. And vaccines are not always safe to give regardless of health status, which is why the other choices don’t fit.