Diseases caused by viruses

• Measles

  • Main symptoms: fever and red skin rash
  • Spreads by the inhalation of droplets from coughs and sneezes and is very infectious, it can cause blindness and brain damage
  • There is no treatment for measles but it can be prevented through vaccination
• HIV

  • HIV initially causes flu-like illness. Unless it is successfully controlled b anti-retroviral drugs the virus attacks the immune system
  • Late stage HIV infection, or AIDS, occurs when the body's immune system becomes so badly damaged it can no longer deal with other infections or cancer
  • HIV is spread by sexual contact or the exchange of body fluids such as blood, which can occur when drug users share needles
• Tobacco mosaic virus

  • Tobacco mosaic virus affects plants and is spread by contact and vectors
  • It damages leaves, and reduced photosynthesis
  • There is no treatment
  • Spread is prevented by field hygiene and pest control