What Causes Infectious Diseases? Small microscopic organisms, also known as pathogens. Pathogens invade the body and attack its cells and tissues. Pathogens take many forms including Viruses, Bacteria, Rickettsias, Protozoan, and Fungi.
How Infectious Diseases are spread….. 1.) People Direct Contact Indirect Contact 2.) Animals 3.) Contaminated Objects 4.) Environment
The Body’s Barriers Against Disease Innate Immune System 1.) Mucous Membranes 2.) Enzymes in tears and saliva 3.) Unbroken skin 4.) Digestive juices 5.) White blood cells
Barriers, cont. Adaptive Immune System 1.) Lymphocytes T cells B cells
Common Infectious Diseases Respiratory Infections 1.) Common Cold- viral 2.) Influenza- viral 3.) Tuberculosis- bacterial 4.) Strep Throat- bacterial
H1N1 virus http://www.cdc.gov/h1n1flu/qa.htm Any questions?
Infectious Diseases, cont. Nervous System 1.) Encephalitis- virus; inflammation of the brain 2.) Meningitis- viral and bacterial; inflammation of membranes that cover the brain and spinal cord 3.) Poliomyelitis- polio; caused by a virus
Other Diseases 1.) Measles- viral 2.) Mononucleosis- viral; spreads through direct contact, mostly “kissing disease” 3.) Hepatitis- mostly viral A- results from eating food or drinking water that has been contaminated; vaccine available. B- more serious than A; spread through contaminated medical instruments, sexual contact with an infected person, and shared needles by infected drug users; vaccine available.
Other Diseases, cont. C- spread through infected blood; can cause liver cancer; no known cure; no vaccine.
Common Sense Measures 1.) Overall good health 2.) Bathe or shower daily 3.) Avoid sharing eating or drinking utensils 4.) Store and prepare food in a safe way 5.) Wash your hands 6.) Cover your mouth when sick, avoid giving disease to someone else 7.) If you are well, avoid contact with sick people
Conclusion Types of pathogens Types of diseases Common senses measures