4.3.1.2 viral diseases

• What are the viral diseases we need to know?

  Measles, HIV and TMV
• what are the symptoms of measles?

  fever and red skin rash
• how is measles spread?

  by inhalation of droplets from sneezes and coughs
• why are young children vaccinated against measles?

  it is a serious illness that can be fatal
• what are the initial symptoms of HIV?

  a flu-like illness
• what does HIV do if not successfully controlled with antiretroviral drugs?

  the virus attacks the body’s immune cells
• What is late stage HIV infection called?

  AIDS
• when does AIDS occur?

  when the body's immune system becomes so badly damaged it can no longer deal with other infections or cancers
• how is HIV spread?

  by sexual contact or exchange of body fluids such as blood which occurs when drug users share needles
• What does TMV stand for?

  Tobacco Mosaic Virus
• what is TMV?

  a widespread plant pathogen affecting many species of plants including tomatoes
• what are the symptoms of TMV in plants?

  It gives a distinctive ‘mosaic’ pattern of discolouration on the leaves which affects the growth of the plant due to lack of photosynthesis