Transcript The Virus
THE West Nile Influenza HIV What is a Virus? • Virus ~ Infectious agent made up of a core of nucleic acid and a protein coat. Virus = Poison • Not a living organism (Must have a HOST) – – – – Is not a cell Does not contain cells Do not eat Does not respond Viral Structure • Does not contain a nucleus • Very small • Composed of three (3) parts – Capsid - Protective coat around core – Nucleic Core – Envelope - layer which surrounds the capsid • Recognizes and binds to host for viral infection Viral Replication • Virus’ do not reproduce they replicate • A host is required for replication – Host ~ organism which shelters or nourishes something by providing materials necessary for viral replication How does a Host become infected? – Envelope contains specific proteins which bind to receptor sites. Viral Infections Influenza, commonly called "the flu," is an illness caused by viruses that infect the respiratory tract. Symptoms: •fever 100° F to 103° F in adults •higher in children •respiratory symptoms such as, •cough, •sore throat, •runny or stuffy nose, •headache, •muscle aches, and •extreme fatigue. Viral Infections Rabies •People usually get rabies from the bite of a rabid animal. •Rabies can be confirmed only in a laboratory. Varicella common name “Chicken Pox” •rash on the skin. •occurs mostly in winter and spring, but can happen any time of the year. •Very contagious •90% of all people in the world will experience chicken pox at some time during their lives, unless they receive the vaccine. Polio •Polio is a disease that is able to damage the nervous system and cause paralysis. •The poliovirus enters the body through the mouth. •Non-paralytic polio will result in fever, vomiting, abdominal pain, lethargy, and irritability. •Some muscle spasms in the neck and back, with muscles generally tender to the touch. •Polio was declared eradicated •in the U.S. in 1979 Measles Symptoms: fever, listlessness, loss of appetite, mild head cold, sore throat, dry cough, and tender lymph gland enlargement in the neck area. Measles rash is a reddish, slightly raised that first appears on the face and neck areas. Mumps It is transmitted mainly by infected saliva. This typically causes enlargement of one or more of the salivary glands. These glands are located on either side of the face, below the ears. The main symptoms are severe swelling and soreness of the cheeks and jaw. Process of injecting a person with a dead or weakened virus which stimulates the immune system to build cells that destroy the invader cell upon next entry DPT: Diphtheria, Pertussis (Whooping cough) & Tetanus Rubeola (Measles) MMR: Combined Measles, Mumps and Rubella Polio Pneumococcal pneumonia Hemophilus meningitis Hepatitis B Rotavirus Foldable (First Side) • Virus- Infectious agent • A host is required for made up of a core of replication. nucleic acid and • Host- organism which protein coat. shelters or nourishes • Not a living organism, something by it must have a host. providing materials necessary for viral replication. Foldable (Second Side) • Viral Structure• Composed of three parts. 1. capsid- protective coat around core 2. nucleic core 3. Envelope- Layer which surrounds the capsid. • • • • • • • Viral Infections Influenza- flu Rabies Chicken Pox Polio Measles and Mumps Thank goodness for vaccines!