Health and Disease Mr. Ramos Introduction to Health & Diseases Health is the state of one’s body. Good health and bad health Disease is anything that can lead to bad health. Diseases in humans are caused by viruses, bacteria, fungi, plants, protists, human genetics, & chemicals. Public Health Public health is the science that deals with protecting and improving the health of people in a community. How to help Teaching people about disease & prevention Providing clean water Vaccination Food & Drug safety Promoting healthy habits Blood Screening Infectious Diseases Infectious diseases can spread from one organism to another. The organisms that cause infectious diseases are called pathogens. A parasite is any organism that lives on or in an organism and harms it. Some pathogens can release toxins to harm. Toxins are poisons. Infectious Diseases: Viruses Viruses are tiny nonliving pathogens. They can have DNA or RNA Contain a protein coat They are intracellular parasites Their life cycle can be lytic or lysogenic Examples: HIV, Flu, Ebola, Herpes, Rabies, Dengue Virus Life Cycle: Lytic & Lysogenic Infectious Diseases: Influenza Flu is short for influenza. The flu is caused by an RNA type virus. Spread: sneezing, coughing, saliva. Symptoms: fever, headaches, sore throat, coughing, severe body aches, and more. Treatment: plenty of rest, drinking water & electrolyte beverages, pain and fever medication, antiviral medication. Antibiotics are not needed. The flu constantly mutates, so you need a flu shot each year Infectious Diseases: HIV HIV stands for Human Immunodeficiency Virus HIV destroys the human immune system and leads to Acquired Immune Deficiency Syndrome (AIDS). HIV is an RNA virus. Spread: sex, blood, semen, breast milk, sharing needles. Target: White Blood Cells (Helper T Cells) Symptoms: fever, swollen lymph nodes, headaches, diarrhea, rash, cough, and many more. Some people are asymptomatic. Treatment: Cocktail of Antiretroviral drugs (no cure for HIV). Infectious Diseases: HIV The best and cheapest way to know if someone has HIV is to check their blood for HIV antibodies. ELISA is a blood test used to determine HIV antibodies. Infectious Diseases: Parasites Disease Parasite Spread By Sleeping Sickness Trypanosoma brucei Bite of an infected tsetse fly Amoebic dysentery Entamoeba histolytica Water or food contaminated by body wastes or untreated sewage Malaria Plasmodium vivax Bite of an infected Anopheles mosquito Roundworm Ascaris lumbricoides Roundworm eggs that are consumed in contaminated food Pinworm Enterobius vermicularis Pinworm eggs that are consumed in contaminated food Infectious Diseases: Chlamydia & Gonorrhea Chlamydia and Gonorrhea are caused by bacteria. Chlamydia is caused by the bacterium Chlamydia trachomatis. Gonorrhea is caused by the bacterium Neisseria gonorrhoeae. Spread: they are sexually transmitted infections Treatment: Antibiotics (people can be cured) Bacterial Gene Transfer: Conjugation Bacteria can exchange information through a process called conjugation. Conjugation is a way to transfer information sexually (remember that bacteria reproduce asexually). “Male” bacteria have are F+. They have a plasmid and a sex pilus. “Female” bacteria are F-. They don’t have a plasmid or sex pilus. Preventing Infectious Diseases Three important ways to prevent infectious diseases: Stay away from sick people Get vaccinated Practice good hygiene A vaccine is a weak or deactivated organism that is placed in the body to trigger an immune response. Noninfectious Diseases Noninfectious diseases are not spread from one organism to another. Some noninfectious diseases are genetic, so they can be passed down from parent to offspring. Examples: Cystic fibrosis, Huntington’s disease, Sickle-cell anemia, Hemophilia, Diabetes, Cancer. Noninfectious Diseases Environment factors & one’s behavior can increase the likelihood for developing these disease. Drinking too much alcohol can cause liver cancer. Eating too much sugar can cause diabetes. Chemicals & polluted air, such as asbestos may cause lung problems.