Lecture Notes on Coronaviruses and Their Impact

Introduction

• Scientists traced a deadly virus to bats in Xitao Cave.
• The virus, a coronavirus, caused the SARS epidemic in 2003.

Overview of Coronaviruses

• Definition: Viruses with protein spikes resembling a crown (corona).
• Types: Hundreds exist, but only seven infect humans.
  • SARS-CoV causes SARS.
  • MERS-CoV causes MERS.
  • SARS-CoV-2 causes COVID-19.
  • Four cause mild, common colds.

Transmission and Infection

• Coronaviruses spread through droplets from coughs.
• Best transmitted in enclosed spaces with people close together.
• Cold weather prolongs virus survival; UV light can damage it.

Virus and Host Interaction

• Protein spikes on virus embed into host cells.
• Virus hijacks host cell machinery for replication.
• RNA vs DNA Viruses
  • RNA viruses have fewer genes, no proofreading mechanism.
  • DNA viruses have a proofreading mechanism.

Mutation and Epidemics

• RNA virus mutations can lead to new virus strains.
• Epidemics often occur when viruses jump from animals to humans.
• In humans, mutations can lead to variations of the original virus.

Characteristics of Coronaviruses

• Some of the largest RNA viruses with many genes.
• Unique enzyme checks and corrects replication errors.
• More stable; slower mutation rate compared to other RNA viruses.

Implications for Treatment and Immunity

• Slow mutation rate suggests better recognition by immune system and vaccines.
• Mutation can reduce effectiveness of vaccines and drugs.
• No approved treatment or vaccine for coronavirus yet.
• Focus on treatments only after epidemics like SARS and MERS began.

Future Concerns and Preparedness

• Encroachment on animal habitats could lead to new coronavirus jumps.
• Investigating unknowns is crucial to prevent devastation.

Conclusion

• The global response included staying home to slow COVID-19 spread.
• TED's global campaign: Celebrate and elevate hopes and ideas of a generation.