Which statement regarding the CYD-TDV (Dengvaxia) vaccine is correct?
- A It is recommended for all children aged 9 years and above irrespective of prior dengue exposure
- B It should be given only to individuals with evidence of previous dengue infection, because vaccinating seronegative recipients increases the risk of severe dengue ✓
- C It is a live attenuated tetravalent vaccine that can be used safely during outbreaks of any single serotype without screening
- D It provides sterilising immunity against all four serotypes and abolishes the need for vector control
Correct answer: B. It should be given only to individuals with evidence of previous dengue infection, because vaccinating seronegative recipients increases the risk of severe dengue
Explanation
Long-term safety data showed that CYD-TDV acts like an asymptomatic primary infection: in dengue-naive recipients a subsequent natural infection behaves like a secondary heterologous infection, carrying higher risk of hospitalisation and severe dengue through antibody-dependent enhancement. Hence licensure and WHO guidance restrict its use to confirmed seropositive individuals. Option C describes the vaccine type correctly but ignores the mandatory screening requirement, so it is false as stated.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.