Viral Diseases

• Examples of viral diseases are Measles, HIV and TMV (Tobacco Mosaic Virus).
• Measles shows symptoms of fever and a rash. It can be fatal. It is prevented by vaccination and is spread by inhalation of droplets from sneezes or coughs
• HIV is initially a flu, but it can mutate and become a virus that attacks the immune system. After the immune system is so badly damaged it can no longer deal with other infections or cancers. It can lead to death. It is spread by sexual contact, exchange of body fluids or sharing of needles.
• TMV (Tobacco Mosaic Virus) is a viral plant disease giving a pattern of discolouration on leaves, affecting growth of the plant due to lack of photosynthesis.