Germs and Disease PDF

Germs and Disease MAIN IDEA​ ​Communicable diseases are caused by germs​. Your head aches. Your nose runs. Your eyes are watery. You have a cough. You have a sore throat. You have a fever. You have a cold. You take some cold medicine and rest for a few days. Your cold is gone. It hasn’t always bee...

Germs and Disease MAIN IDEA​ ​Communicable diseases are caused by germs​. Your head aches. Your nose runs. Your eyes are watery. You have a cough. You have a sore throat. You have a fever. You have a cold. You take some cold medicine and rest for a few days. Your cold is gone. It hasn’t always been this easy to recover from an illness or disease. Scientists study diseases and illnesses and try to come up with treatments. In some cases, they have come up with medicines that prevent diseases. A cold is one type of disease​. ​A disease like a cold that can spread from one person to another is called a communicable disease. Communicable diseases are caused by pathogens​. ​You probably know them as germs​. Another category of disease is a noncommunicable disease. Germs are all around us. Some germs are not harmful. When a harmful germ, or pathogen, enters your body, it can multiply and cause an infection. Types of Pathogens Pathogens are not all alike. However, all pathogens can cause disease. There are four main types of pathogens: viruses (VY ruh suhz), bacteria (bak TIR ee uh), fungi (FUHN jy), and protozoa (proh tuh ZOH uh). Viruses are so tiny they can only be seen with a special microscope. Viruses are not alive. They are usually made up of genetic material and protein. Some strains, or types, of viruses are not harmful. Other types can cause diseases such as the common cold, flu, upper respiratory infections, and measles. Most infections caused by viruses cannot be cured with antibiotics. The most harmful viruses can cause serious diseases. AIDS and hepatitis are serious diseases caused by viruses. AIDS is an immune system disorder. Hepatitis is a disease of the liver. Bacteria are everywhere. Some of these simple one-celled organisms are helpful to humans. For example, the bacteria in your digestive tract help you break down the food you eat. Other bacteria live on your skin and help prevent harmful bacteria from infecting you. Some bacteria, though, is harmful. Harmful bacteria can cause diseases such as pneumonia and strep throat. Most infections that are caused by bacteria can be treated with antibiotics. Fungi cannot make their own food. So they must break down other organisms and absorb their nutrients. Most fungi are harmless to humans. Mushrooms, for example, are fungi. Some mushrooms are safe for humans to eat. Molds and yeast are also fungi. Fungi like to live in warm and moist places. They can cause a variety of diseases. Athlete’s foot and ringworm are caused by fungi. Fungi can also cause serious lung infections. Protozoa are also one-celled organisms but are more complex than bacteria. Some protozoa, called parasites, attach themselves to healthy cells. They rob the cell of nutrients, but they don’t kill the cell. Some protozoa cause serious illnesses in humans. One of the most well-known and deadly diseases caused by protozoa is malaria. Malaria is found in tropical regions. It is spread to humans by infected mosquitoes. If an infected mosquito bites a person, the protozoa are transferred into the body through the skin. The figure located in the Lesson Resources panel shows some kinds of pathogens and lists the diseases they cause. READING CHECK Compare​ How are viral infections different from bacterial infections? How Pathogens Spread How can you keep from being infected by a communicable disease? Well, to understand how to avoid becoming infected, it’s important to understand how pathogens are spread. There are four main ways pathogens are spread. Direct contact One of the most common ways pathogens are spread is by physically touching another person. For example, if someone with a cold sneezes into his right hand and then you shake hands with him; you will likely get cold pathogens from him. Shaking hands with him passes along the germs that are on his skin. Washing your hands often with soap can help stop the spread of pathogens. Some pathogens are spread through contact with infected blood. People can come into contact with infected blood by injecting drugs using a needle that someone else has used. Dirty needles used for tattooing or piercing can also spread pathogens. It is also possible for the blood of an infected person to infect someone else if the blood comes into contact with broken skin. Some pathogens are spread through sexual contact. Abstinence is the best way to prevent sexually transmitted diseases. Indirect contact If someone sneezes or coughs, pathogens are spread through the air. It is important to use tissues to cover your nose when you sneeze and your mouth when you cough. Pathogens are also spread when people share certain items. Drinking glasses and eating utensils should never be shared. Other items such as toothbrushes and razors should not be shared. Contact with animals or insects Animals and insects can spread pathogens. An organism that transmits pathogens is a vector​.​ If an animal is sick with rabies, for example, that animal can spread rabies if it bites someone or another animal. Insects spread many diseases. For example, infected deer ticks can spread Lyme disease. Infected mosquitoes can spread malaria or West Nile virus. Using insect repellent when you go outdoors can help protect you from insect bites. Contaminated food and water Bacteria that cause food poisoning can be spread through contaminated food or water. If the contaminated food or water is eaten or drunk, the pathogens spread into the individual. If food is undercooked or improperly stored, pathogens can grow. The pathogens can cause illness. Illnesses caused by contaminated foods are called foodborne illnesses. To help prevent foodborne illnesses, make sure meat is fully cooked. Undercooked meat may contain bacteria that will make you ill. Remember to properly store foods that can spoil. This includes dairy products and meat. You should also wash fruits and vegetables. Many food packages say the product has been washed. However, it never hurts to wash it yourself. Meat, poultry, fish, and eggs need to be handled carefully. Bacteria from raw meats and eggs can spread on your food preparation surface. Keeping your food preparation area clean is very important. You should always wash knives and surfaces that meat, poultry, fish, and eggs have touched. Use warm, soapy water to clean food preparation surfaces. READING CHECK Identify​ What are four ways pathogens are spread? Stopping the Spread of Pathogens MAIN IDEA​ ​Practicing certain healthy behaviors can stop the spread of pathogens​. Although you can’t completely stop the spread of pathogens, you can protect yourself and others from the spread of pathogens. Good personal hygiene is one of the best ways to help stop the spread of pathogens. You can also help stop their spread by eating nutritious foods and getting enough sleep. Engaging in regular, physical activity will also help your body fight pathogens. Keep your environment, the space around you, clean. This will also keep down the number of pathogens. Stopping the spread of pathogens will help to protect your health and the health of others. Protecting Yourself So, what can you do to protect yourself from pathogens? In addition to the tips mentioned above, follow these guidelines to help keep yourself from getting sick. Keep your distance from people who are sick with a communicable disease. Be especially careful if they are still contagious​. Do not share eating or drinking utensils or toothbrushes or other personal hygiene items. Wash your hands thoroughly in warm soapy water before preparing or eating food. It is important to wash after using the bathroom, playing with pets, and visiting a sick person. It is also necessary to wash after touching trash or garbage or other sources of pathogens. Keep your hands and fingers away from your mouth, nose, and eyes. Don’t bite your fingernails. Handle and prepare food safely. This is especially important for meats, fish, and poultry. Eggs should be handled carefully, too. Meats, fish, poultry, and eggs should be cooked thoroughly. Wash vegetables and fruits before eating. Wash counters thoroughly with paper towels or a clean sponge or cloth. If you use a sponge or cloth, clean them thoroughly and frequently. Using sponges and cloths repeatedly can spread more germs than they remove. Keep your environment clean. Empty the trash often. Keep the trash cans clean. Clean up after your pets. Another way to maintain good health is to practice healthy lifestyles. If you are exposed to pathogens, a healthy lifestyle can help you avoid getting sick. These healthy lifestyle practices include the following. Eat a balanced diet. Bathe or shower regularly using soap. Be sure to wash your hair using shampoo. Avoid tobacco products, alcohol, and other drugs. Get 8-9 hours of sleep every day. Rest when you are sick. Check with parents or guardians to make sure your immunizations are up to date. Manage your stress well. Learn ways to relieve your stress. Too much stress can weaken your immune system and make you more vulnerable to communicable diseases. Get regular physical checkups. Talk with your doctor if you have questions. Protecting Others You might be carrying pathogens and not realize it. You may have a communicable illness that hasn’t shown symptoms yet. If you come into contact with others, you can easily spread the pathogens. Help protect the people you come into contact with. Think ahead and follow these healthful behaviors. If you are sick, stay home and away from others. Tell your parent or guardian and get medical help if you need it. If you become ill at school, let the school medical personnel know as soon as possible. Getting medical help early can keep the illness from getting too bad. It can also help keep it from spreading. When you sneeze or cough, cover your mouth with a tissue. Only use the tissue once. If you don’t have a tissue, what should you do? Sneeze or cough into the crook of your elbow. This helps to keep pathogens from spreading. Wash your hands immediately after you sneeze or cough. If you have a prescription to take medication, follow the directions exactly. Take all of the medicine you are supposed to take. If you stop taking the medicine before you are supposed to, you might become sick again. READING CHECK Analyze​ What personal health care practices can prevent the spread of communicable diseases? Keep It to Yourself When you have a cold, take action to prevent spreading your cold to others. Be careful to cover your mouth and nose when you cough or sneeze. Keep as much distance between yourself and others as you can. Avoid sharing cups, utensils, or other personal items.