Viral diseases

Viral diseases Viruses are the smallest intracellular obligate parasites, which multiply within Common cold is caused by more than different strains of Rhino viruses. More over their RNA genome keeps changing due to mutation. Hence it is very difficult to prepare a common vaccine for the disease. XII Std Biology-Zoology Chapter- XII Std Biology-Zoology Chapter- Human Health and Diseases S. No Diseases Causative agent Site of infection Mode of transmission Symptoms Common cold Rhino viruses Respiratory tract Droplet infection Nasal congestion and discharge, sore throat, cough and headache Mumps Mumps virus (RNA virus), Paramyxo virus Salivary glands Saliva and droplet infection Enlargement of the parotid glands Measles Rubeola virus (RNA virus), Paramyxo virus Skin and respiratory tract Droplet infection Sore throat, running nose, cough and fever, reddish rashes on the skin, neck and ears Viral hepatitis Hepatitis - B virus Liver Parenteral route, blood transfusion Liver damage, jaundice, nausea, yellowish eyes, fever and pain in the abdomen Chicken pox Varicella -Zoster virus (DNA Virus ) Respiratory tract, skin and nervous system Droplet infection and direct contact Mild fever with itchy skin, rash and blisters Poliomyelitis Polio virus (RNA virus) Intestine, brain, spinal cord Droplet infection through faecal oral route Fever, muscular stiffness and weakness, paralysis and respiratory failure Dengue fever (Break bone fever) Dengue virus or Flavi virus (DENV - virus) Skin and blood Mosquito vector Aedes aegypti Severe flu like illness with a sudden onset of fever and painful headache, muscle and joint pain Chikungunya Alpha virus (Toga virus) Nervous system Mosquito vector Aedes aegypti Fever and joint pain, headache and joint swelling Table: . Viral diseases in human beings XII Std Biology-Zoology Chapter- XII Std Biology-Zoology Chapter- Human Health and Diseases Swine flu was first recognised in the pandemic and still circulates as a seasonal flu virus. Swine flu is caused by the H1N1 virus strain. Symptoms include fever, cough, sore throat, chills, weakness and body aches. Children, pregnant women