As the monsoon season returns, so does the heightened risk of dengue, a mosquito-borne disease that affects thousands of people across India every year. With rising infections during the rainy months, the approval of India's first dengue vaccine, QDENGA, marks a significant development in the country's fight against the disease.

The Drugs Controller General of India (DCGI) has approved QDENGA, a vaccine developed by Japanese pharmaceutical company Takeda, for use in India. One of its most notable features is that people do not need to undergo prior dengue infection testing before receiving the vaccine, setting it apart from some earlier dengue vaccines.

While health experts consider the approval an important milestone, they also stress that vaccination is only one part of dengue prevention. Mosquito control, early diagnosis, and timely medical care remain equally important.

What Is QDENGA?

QDENGA is a live attenuated dengue vaccine, meaning it contains weakened forms of the dengue virus that cannot cause the disease but are capable of stimulating the body's immune system.

Once administered, the vaccine helps the immune system produce protective antibodies. If the vaccinated person is later exposed to the actual dengue virus, the immune system is better prepared to respond, reducing the risk of severe illness.

A major advantage of QDENGA is that it is designed to provide protection against all four dengue virus serotypes:

• DENV-1
• DENV-2
• DENV-3
• DENV-4

Protection against multiple serotypes is considered important because infection with different dengue strains can increase the risk of severe disease.

Why Is the "No Pre-Test" Feature Important?

Previous dengue vaccines available globally often required individuals to first undergo blood testing to confirm whether they had previously been infected with dengue.

This was necessary because, in certain circumstances, vaccinating people who had never contracted dengue could increase the risk of severe disease during a future infection.

According to available clinical evidence, QDENGA has demonstrated safety in individuals regardless of whether they had previously been infected with dengue. This removes the need for routine pre-vaccination screening, making large-scale vaccination programs easier to implement.

Experts believe this feature could be especially valuable in countries like India, where conducting prior blood tests for millions of people would be challenging.

Clinical Trials and Effectiveness

Takeda evaluated the vaccine in large international clinical trials involving more than 20,000 children and adults.

According to trial data:

• The vaccine reduced the risk of hospitalization due to dengue by up to 84%.
• It lowered the overall risk of symptomatic dengue infection by approximately 61%.

While these results are encouraging, experts note that vaccine effectiveness may vary depending on factors such as age, previous exposure to dengue, circulating virus strains, and local epidemiological conditions.

Who Can Receive the Vaccine?

Under the approved guidelines, QDENGA can be administered to individuals between 6 and 60 years of age.

The vaccination schedule consists of two doses, with an interval of three months between them.

The vaccination process works as follows:

• First dose: Initiates the body's immune response against dengue.
• Second dose: Strengthens and extends long-term protection.

Completing both doses is important for achieving the intended level of immune protection.

Expected Price and Availability

Takeda has not yet officially announced the retail price of QDENGA in India.

However, industry sources indicate that each dose may cost approximately ₹4,000 to ₹5,000, though the final pricing could vary after commercial launch.

Initially, the vaccine is expected to become available through private hospitals and clinics.

The government has not yet announced whether QDENGA will be included in India's national immunization programme or the timeline for any public-sector rollout.

Will the Vaccine Be Manufactured in India?

Initially, QDENGA will be imported from Germany.

Takeda has partnered with Biological E. for the Indian market, while manufacturing is currently being carried out at Takeda's production facility in Singen, Germany, along with its manufacturing partner IDT Biologika GmbH.

Industry experts believe that increased production and local partnerships may improve availability over time and could eventually help reduce costs.

Does the Vaccine Eliminate Dengue Completely?

Health experts caution that the vaccine should not be viewed as a complete solution to dengue.

The primary objective of vaccination is to:

• Reduce the risk of severe dengue.
• Lower hospitalization rates.
• Decrease dengue-related deaths.

However, vaccination alone cannot eliminate dengue transmission.

Experts continue to recommend:

• Preventing mosquito breeding by avoiding stagnant water.
• Using mosquito repellents and protective clothing.
• Installing window screens or mosquito nets.
• Seeking prompt medical attention if dengue symptoms develop.

A comprehensive public health approach remains essential for controlling the disease.

Dengue Continues to Be a Major Public Health Challenge

According to the National Centre for Vector Borne Disease Control (NCVBDC), dengue continues to pose a significant health burden in India.

Official data indicate:

• 2023: More than 289,000 dengue cases and around 1,200 deaths.
• 2024: Over 310,000 reported cases and more than 1,400 deaths.

These figures highlight the continuing impact of dengue across the country, particularly during the monsoon season.

Medical Community Welcomes the Approval

Healthcare professionals have described the approval of QDENGA as an important advancement in dengue prevention.

Some experts believe the vaccine has the potential to significantly reduce severe illness and dengue-related mortality if used alongside existing public health measures. However, they emphasize that continued mosquito control, public awareness, and timely treatment will remain essential components of dengue prevention.

The Bottom Line

The approval of QDENGA, India's first dengue vaccine, represents a significant step forward in combating one of the country's most widespread mosquito-borne diseases. Its ability to protect against all four dengue virus serotypes and its use without requiring prior dengue testing distinguish it from earlier vaccines.

While vaccination offers a promising tool to reduce severe disease and hospitalizations, experts stress that it is not a substitute for mosquito control or early medical care. Combining vaccination with preventive measures, prompt diagnosis, and community awareness will be key to reducing the impact of dengue in the years ahead.