India approves dengue vaccine: Doctor explains the four virus strains and why immunity remains a major challenge - The Times of India

What the report says

The Times of India reported that India has approved its first dengue vaccine, QDENGA (TAK-003), developed by Takeda Biopharmaceuticals India, for use among people aged 4 to 60. According to the report, the vaccine is given in two doses three months apart, is intended to protect against all four dengue virus serotypes — DENV-1, DENV-2, DENV-3 and DENV-4 — and does not require screening for previous dengue infection before vaccination.

The article, updated July 20, 2026, framed the approval in the context of India’s monsoon season, when dengue cases commonly rise. It explained that dengue immunity is unusually complex because infection with one serotype generally gives long-term protection only against that same serotype. Dr Raj Kumar, Senior Consultant in Pulmonary Medicine at ISIC Multispeciality Hospital, told TOI Health that people can still be infected later by any of the remaining strains.

TOI also highlighted why repeat infections may sometimes carry higher risk. The report referred to antibody-dependent enhancement, a process in which antibodies from an earlier infection may fail to fully neutralize a different dengue serotype and could contribute to more severe illness in some cases. The article stressed, however, that not every second infection becomes severe.

The report said vaccination should follow national guidance and medical advice, and that it should not replace mosquito-control measures. Dr Kumar advised continued use of repellents, long clothing, mosquito nets and removal of stagnant water where Aedes mosquitoes breed. The article also urged people with high fever, severe headache, pain behind the eyes, joint pain, nausea, vomiting or rashes to seek medical care promptly.