Presentation on theme: "Chapter 13- Infectious Diseases"— Presentation transcript:
1 Chapter 13- Infectious Diseases Section 1- What are Infectious Diseases?Section 2- Protecting Yourself from Infectious DiseasesSection 3- Common Infectious Diseases
2 Objectives for Chapter 13 Identify different agents that cause infectious diseasesList four ways infectious diseases spreadDescribe different treatments for infectious diseasesDescribe how the body fights infectious diseasesSummarize five things a person can do to stay well
3 Objectives cont. Describe how immunity to a disease develops State three things you should do when you are sickList three things you can do to prevent the spread of infectious diseases
4 Infectious DiseasesAn infectious disease is any disease that is caused by an agent that has invaded the body.Examples of infectious diseases: colds, the flu, head lice, and tuberculosisAll infectious diseases are caused by pathogensA pathogen is any agent that causes disease.
5 Bacteria Tiny, single-celled organisms Most bacteria are harmless, many are actually helpfulSome bacteria make you sick when they grow inside your bodySome bacteria give off poisons, while other bacteria enter and damage cellsTuberculosis, tetanus, and sinus infections
6 Viruses Smaller than bacteria Tiny, disease-causing particles made up of genetic material and a protein coatThe genetic material contains instructions for making more virusesViruses survive and replicate only inside living cellsChicken pox, colds, the flu, measles, and HIV
7 FungiAn organism that absorbs and uses the nutrients of living or dead organismsAthlete’s foot- caused by a fungus that lives and feeds on your feet and makes them burn and itchRingworm- a fungus responsible for a scaly, circular rash
8 ProtozoansSingle-celled, microscopic organisms that are larger and more internally complex than bacteriaProtozoans account for diseases that are the leading causes of death throughout some parts of the worldMalaria is a disease caused by protozoans
9 ParasitesAnimal parasites get their energy and nutrients by feeding on other living thingsExamples of harmful animal parasites include head lice, tapeworms, and certain roundworms
12 How are Infectious Diseases Spread? Person-to-person- through the air or contact with another personexamples: flu, colds, measlesFood-and-water- through the food you eat or the water you drink.examples: hepatitis A, botulism, typhoid, choleraEnvironment- from the objects around you example: tetanusAnimals- from animals or insectsexamples: ringworm, malaria, Lyme disease
13 Treating Infectious Diseases Bacterial diseases- antibioticsViral diseases- most medications rely on relieving symptoms and stopping the production of viruses inside the human cellsFungal infections- over-the-counter antifungal medicineProtozoan infections- prevention is the keyParasitic infections- medications
14 Protecting Yourself from Infectious Diseases Chapter 13 Section 2
15 How Your Body Fights Disease Your body’s first line of defense includes your skin, mucous membranes, and chemicals.Skin keeps pathogens from entering your bodyMucous membranes, such as your nose, mouth, and throat, trap pathogens and move them to your stomach to be destroyed.Your sweat, tears, and stomach acid are all chemicals that kill bacteria
16 Inflammatory Response Your body’s second line of defense is inflammation.Inflammation- a reaction to injury or infection that is characterized by pain, redness, or swelling.This is caused by the small blood vessels that expand to bring more blood to the injured areaThis response shows that your body is attacking pathogens
17 Immune System This is your third line of defense The immune system is made up of certain types of blood cells and certain proteins called antibodies.These infection-fighting cells move through the lymphatic system, a network of vessels that carry a clear fluid called lymph throughout the body.
18 White blood cells are cells in the blood whose primary job is to defend the body against disease. When you are sick, your lymph nodes often swell because of the growing number of white blood cells fighting the infection.Active immunity is established when the body produces antibodies that recognize future pathogens (either by having the disease or by vaccination)
19 What You Can Do to Stay Well Protect yourselfEat a healthy, balanced dietDrink waterReduce your stress levelsExercise regularlyGet regular medical checkupsTry to avoid close contact with sick peopleGet enough sleep
20 Get VaccinatedVaccines are substances usually prepared from killed or weakened pathogens or from genetic material and that is introduced into a body to produce immunity.When a vaccine is injected, the immune system responds by making white blood cells called memory cells.In the future, if the pathogen enters the body, the memory cells and their antibodies fight the pathogen before it can cause disease.
21 What to Do When You Are Sick Stay homeGet plenty of restTry not to pass your illness to othersDon’t share personal itemsCover your mouthDrink plenty of fluidsSee a doctor and take the doctor’s adviceTake medications that are prescribed to youWash your hands frequently