Dengue Virus: Serotypes, Vaccines and UPSC Notes

UPSC Mapping

Exam	Topics
Prelims	Dengue Virus, Serotypes, Vector-borne Diseases
Mains	GS Paper II – Public Health

Pathogen	Serotypes	Source
Dengue Virus (DENV)	DENV-1, DENV-2, DENV-3, DENV-4	ICMR-VRDL

What is Dengue Virus?

Dengue Virus is the causative agent of dengue fever, a mosquito-borne viral disease. According to the ICMR’s Virus Research and Diagnostic Laboratory (VRDL), all four dengue virus serotypes—DENV-1, DENV-2, DENV-3 and DENV-4—are currently circulating in India.

A serotype is a classification of microorganisms based on the antigens or other molecules present on their surface. Different serotypes of the same virus can trigger different immune responses while belonging to the same species.

Why is Dengue Virus in News?

The ICMR-VRDL network has detected the simultaneous circulation of all four dengue virus serotypes in India, highlighting the importance of continuous surveillance and public health preparedness.

The development has also renewed interest in dengue vaccine research and India’s strategy for preventing vector-borne diseases.

Key Features

• Four circulating serotypes: DENV-1, DENV-2, DENV-3 and DENV-4 are all present in India.
• Serotype classification: Serotypes are distinguished based on differences in surface antigens or related molecular characteristics.
• ICMR surveillance: The Virus Research and Diagnostic Laboratory (VRDL) network monitors dengue virus circulation and supports disease surveillance.
• Public health significance: Simultaneous circulation of multiple serotypes underlines the importance of surveillance, diagnosis and clinical preparedness.

Vaccine Status in India

India currently does not include a dengue vaccine in its Universal Immunisation Programme (UIP).

• Indigenous development: Indian vaccine candidates are in advanced stages of clinical development.
• Regulatory approval: An internationally approved dengue vaccine has recently received regulatory clearance for import and sale in India.
• Future potential: Vaccine availability may strengthen dengue prevention alongside surveillance and vector-control measures.

Way Forward

Strengthening disease surveillance, accelerating vaccine development and maintaining effective mosquito-control programmes will remain essential for reducing the dengue burden. Public awareness regarding preventive measures should complement scientific advances.

Continued monitoring by ICMR and timely vaccination strategies, whenever adopted, can improve India’s preparedness against dengue outbreaks. Official information is available through the Indian Council of Medical Research and the Ministry of Health and Family Welfare.

Prelims Practice Corner

Q1. How many dengue virus serotypes are currently circulating in India according to ICMR?

(a) One (b) Two (c) Three (d) Four

Answer: (d) DENV-1 to DENV-4 are circulating.

Q2. A serotype is classified primarily on the basis of?

(a) Genome size (b) Surface antigens or related molecules (c) Shape only (d) Mode of transmission

Answer: (b) Surface antigens or related molecules.

Q3. Which organisation’s VRDL network reported the circulation of all four dengue serotypes?

(a) WHO (b) ICMR (c) NITI Aayog (d) DBT

Answer: (b) ICMR.

Q4. Dengue vaccine is currently included in India’s Universal Immunisation Programme.

(a) True (b) False

Answer: (b) False.

Q5. Indigenous dengue vaccine candidates in India are?

(a) Discontinued (b) In advanced stages of clinical development (c) Already part of UIP (d) Not under development

Answer: (b) In advanced stages of clinical development.

Mains Practice Questions

Q1. Discuss the importance of disease surveillance and vaccine development in controlling vector-borne diseases such as dengue. (10 marks)

Answer Structure

• Intro: Explain the public health burden of dengue.
• Body: Surveillance, serotypes, vaccine development and preventive strategies.
• Conclusion: Strengthen integrated vector management and immunisation preparedness.

Q2. Evaluate India’s preparedness to tackle emerging vector-borne diseases through scientific research and public health interventions. (15 marks)

Answer Structure

• Intro: Explain the significance of vector-borne diseases.
• Body: Surveillance networks, vaccine research, healthcare infrastructure and challenges.
• Conclusion: Emphasise coordinated disease control strategies.

FAQs on Dengue Virus

What are dengue virus serotypes?

Dengue virus has four recognised serotypes—DENV-1, DENV-2, DENV-3 and DENV-4—which are classified based on differences in surface antigens.

Is there a dengue vaccine in India’s Universal Immunisation Programme?

No. India currently does not include a dengue vaccine in its Universal Immunisation Programme, although indigenous vaccine candidates are in advanced clinical development.

What did the ICMR-VRDL network report?

The ICMR’s Virus Research and Diagnostic Laboratory network reported that all four dengue virus serotypes are currently circulating in India.