Describe the components and functioning of a vaccine.
In short
A vaccine combines an antigen (live attenuated, inactivated, sub-unit, DNA, mRNA or viral vector) with adjuvants, stabilisers, preservatives and a sterile diluent. It functions by simulating infection without disease, prompting memory B and T cells that respond rapidly on real exposure and build herd immunity.
Model answer
Ghissu Editorial · Verified 4 Oct 2026 · 303 words
Regulatory Oversight
CDSCO balances safety and speed, approving vaccines like Covaxin developed with Vero Cell technology, accelerating COVID-191 response. Emergency use authorisations enabled rapid deployment while maintaining safety standards.
Manufacturing Capacity
India’s hubs in Pune and Hyderabad scale production, with Serum Institute producing Covishield for domestic and global needs. This capacity supports India’s role as the “pharmacy of the world” and addresses global vaccine demand.
Challenges in Functioning
HPV Vaccine Hesitancy2 in rural India shows gendered mistrust and social resistance; misinformation and logistical barriers affect uptake. Nutritional and genetic factors also influence vaccine efficacy, complicating uniform protection.
Coverage and Accessibility
Immunisation coverage improved from 35% to over 76%, with Andhra Pradesh’s immunisation efforts aiding progress through targeted outreach and infrastructure development. However, disparities persist across regions and socio-economic groups.
Cold Chain and Monitoring
Robust cold chain and digital tools like CoWIN enhance delivery; surveillance tracks safety and pathogen mutations. The One Health Mission supports monitoring zoonotic diseases critical for vaccine strategy adjustments.
Integrating Vaccination and Awareness3
Combining HPV vaccination with community sensitisation can overcome hesitancy, as seen in government campaigns addressing misinformation and social resistance.
Strengthen Indigenous R&D
Boost funding and innovation to sustain vaccine development and deployment, building on initiatives like the COVID Suraksha Mission to enhance India’s vaccine self-reliance.
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This chapter in the exam
Human diseases; genetic engineering basics; biotechnology in agriculture; vaccines54 questions
Asked in 8 of 8 sittings since 2008
Most tested: Vaccines and immunisation, alongside GM crops/biotech agriculture.
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Question from the official APPSC Group-I Mains 2025 paper. Answer written by Ghissu's engine and checked against our editorial standards. Found an error? Tell us and we correct it within 48 hours.