CURRENT AFFAIRS | MARCH 2026
CLAT Relevance
Key points for GK section: RNA vs DNA virus distinction, mutation basics, antigenic drift vs shift, WHO Disease X, IHR, GHSA — science-based GK frequently tested in CLAT.
Key points for GK section: RNA vs DNA virus distinction, mutation basics, antigenic drift vs shift, WHO Disease X, IHR, GHSA — science-based GK frequently tested in CLAT.
RNA vs DNA Viruses — Basic Distinction
| Feature | RNA Viruses | DNA Viruses |
|---|---|---|
| Genetic material | RNA | DNA |
| Mutation rate | Very high | Low |
| Proofreading | Absent | Present |
| Examples | Influenza, COVID-19, Nipah, Ebola, HIV, Dengue | Smallpox, Herpes, Hepatitis B |
| Pandemic risk | Higher | Lower |
Key Fact: RNA viruses mutate up to 1 million times faster than DNA viruses because RNA polymerase lacks proofreading ability — meaning errors during replication are not corrected.
Why RNA Viruses Are a Global Threat
- Rapid mutation — creates new variants that evade immunity
- Vaccine escape: Mutations can render vaccines less effective (e.g., influenza variants)
- Drug resistance: HIV, Hepatitis C develop resistance through mutations
- Cross-species jumping: High mutation rate enables host switching (zoonotic spillover)
- Pandemic potential: All major pandemics in 100 years caused by RNA viruses — Spanish Flu, H1N1, COVID-19
Antigenic Drift vs Antigenic Shift
- Antigenic drift: Gradual, small mutations in viral surface proteins — causes seasonal epidemics (e.g., flu season changes)
- Antigenic shift: Major reassortment of genetic segments — creates entirely new strains — causes pandemics
- Drift = minor change; Shift = major change
- Influenza is most prone to both drift and shift (segmented genome)
Nipah as an RNA Virus
- Type: Single-stranded, negative-sense RNA virus
- Family: Paramyxoviridae, genus Henipavirus
- Non-segmented genome — less prone to shift, but drift remains a concern
- Closely related to Hendra virus (Australia)
- WHO priority pathogen for R&D — no approved vaccine or antiviral
CLAT Angle: Distinguish RNA vs DNA viruses, know key examples of each, understand antigenic drift vs shift, and remember WHO/IHR frameworks. These are high-value science GK questions.
Global Health Security Framework
- WHO Disease X: A placeholder for an unknown pathogen that could cause a future pandemic
- IHR (International Health Regulations 2005): Legally binding on 196 countries — requires disease reporting to WHO
- GHSA (Global Health Security Agenda): Launched 2014 — 70+ countries collaborating on pandemic preparedness
- Pandemic Treaty (under negotiation): New WHO treaty for equitable vaccine access and pathogen sharing
- India’s role: Member of GHSA, established National Centre for Disease Control (NCDC) and ICMR for surveillance
Quick Revision Points
- RNA viruses mutate faster — no proofreading in RNA polymerase
- Antigenic drift = gradual mutation; Shift = major reassortment
- Nipah = ssRNA, Paramyxoviridae
- COVID-19 = ssRNA, Coronaviridae
- Disease X = unknown future pandemic pathogen
- IHR maintained by WHO, binding on 196 countries
- GHSA launched: 2014
Source: UPSC Essentials, The Indian Express — March 2026
Practice Quiz — 10 CLAT-Style Questions
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