viruses

• What is a virus?

  A genetic material surrounded by a protein coat
• What does it mean that a virus is an obligate intracellular parasite?

  It must infect a host cell to reproduce
• Are viruses considered alive? Why or why not?

  No, they cannot grow or produce energy
• What are the two main components of a virus?

  Viral genome and viral capsid
• What is the function of the viral capsid?

  It protects the viral genome
• What is a viral envelope and its significance?

  A lipid bilayer that helps bind to cells
• What is the classification hierarchy of viruses?

  Order-Family-Subfamily-Genus-Species
• What are some examples of viral classifications?

  • Nidovirales-Coronaviridae-Betacoronavirus-Sarbecovirus
  • Mononegavirales-Paramyxoviridae-Morbillivirus
  • Mononegavirales-Pneumoviridae-Orthopneumovirus
• What percentage of child mortality in LMIC is caused by measles?

  10%
• How many deaths did the 1918 influenza pandemic result in?

  ~20 million deaths
• How many people were living with HIV in 2012?

  34 million people
• What is the economic impact of plant viruses?

  ~£40 billion worth of crop losses annually
• What are the two types of virus transmission?

  Horizontal and vertical transmission

  
• What are the mechanisms of virus transmission?

  • Direct contact
  • Aerosols
  • Contaminated surfaces
  • Exchange of body fluids
  • Insects
  • Contaminated food and water
• What types of treatments exist for viral diseases?

  Antivirals and vaccinations
• Why are vaccines considered a longer-term solution?

  They provide immunity against specific viruses
• What are the types of vaccines mentioned?

  • Live attenuated (measles)
  • Inactivated (Rabies)
  • Subunit (HepB)
  • Conjugate (Haem Inf B)
  • Genetic (viral vector, mRNA, DNA)
• How long do vaccines usually take to develop?

  ~10 years
• What is a non-pharmaceutical intervention for virus control?

  Isolation of the infected individuals
• What are key points about viruses?

  • Obligate intracellular parasites
  • Infect all living things
  • Genetic material surrounded by a protein coat
  • Huge burden of viral disease
• What is a virome?

  All viruses living with an organism or environment
• What is part of the microbiome?

  The virome
• What is the virosphere?

  The sum of all viruses on Earth
• How much of our cells are human?

  Only ~43% of the cells are human
• How many bacteria are in the human body?

  ~1.10x10^14
• How many viruses are in the human body?

  ~1.10 x 10^ 15
• What percentage of our DNA is made of virus genetic material?

  5-8% of our DNA
• What is endogenous retrovirus?

  Virus genetic material acquired through infection
• How long have viruses been infecting humans?

  Viruses are older than humans
• When did herpes viruses first infect human ancestors?

  Over 80 million years ago
• How have viruses played a role in human evolution?

  They contributed to the development of the placenta
• What are the ways viruses can affect us?

  Acute infection, long-term infections, oncogenesis
• What is an example of an acute infection?

  Flu virus infection
• What is an example of a long-term infection?

  HIV infection
• What is an example of oncogenesis?

  HPV leading to cervical cancer
• Why is it important to identify new viruses?

  To understand causes of human disease
• What is metagenomics?

  Sequencing all genetic material to find viruses
• What is zoonosis?

  When a virus jumps from animal to human
• What percentage of new infectious diseases are zoonoses?

  75% of newly emerging infectious diseases
• What is an example of zoonosis?

  SIV to HIV transmission