Human Health Objective: 1st period ► Describe causes, transmission, and prevention of common viral, bacterial, and parasite diseases (e.g., influenza, measles, HIV, COVID-19, tetanus, malaria). What are Diseases? ► A disease is an abnormal condition affecting a healthy living organism. It is broadly divided into infectious and non-infectious. ► https://www.youtube.com/watch?v=8919Zm8Gi4U Infectious diseases ► Infectious diseases are diseases that spread from person to person. They are caused by pathogens such as bacteria, viruses or fungi. Viral infections. ► Viruses are a piece of information (DNA or RNA) inside of a protective shell (capsid). ► Viruses are much smaller than your cells and have no way to reproduce on their own. ► They get inside your cells and use your cells’ machinery to make copies of themselves. Bacterial infections ► Bacteria are single-celled organisms with their instructions written on a small piece of DNA. ► Bacteria are all around us, including inside of our body and on our skin. ► Many bacteria are harmless or even helpful, but certain bacteria release toxins that can make you sick. Common infectious diseases caused by viruses: Flu (Influenza) ► The flu is a common respiratory illness you get from the influenza virus. Symptoms often include fever, head and body aches, coughing and a stuffy or runny nose. ► The influenza virus spreads from direct or indirect contact with someone else who’s infected. Such as : someone nearby coughing, sneezing or talking, By touching a surface that’s contaminated by the flu virus. Measles ► Measles is a highly contagious, serious disease caused by a virus. ► It is normally passed through direct contact and through the air. The virus infects the respiratory tract, then spreads throughout the body. Measles is a human disease and is not known to occur in animals. ► The first sign of measles is usually a high fever, which begins about 10 to 12 days after exposure to the virus. ► A runny nose, a cough, red and watery eyes, and small white spots inside the cheeks can develop in the initial stage. After several days, a rash erupts, usually on the face and upper neck. Over about 3 days, the rash spreads, eventually reaching the hands and feet. ► Serious complications are more common in children under the age of 5, or adults over the age of 30. ► Routine measles vaccination for children is a way to prevent the disease. HIV ► HIV (human immunodeficiency virus) is a virus that attacks the immune system. The immune system becomes weaker, making it harder for the body to fight off infections and some kinds of cancers. ► HIV spreads when infected blood or body fluids. This can happen: ► through sharing needles for injecting drugs or tattooing ► by getting stuck with a needle with an infected person's blood on it. ► First symptoms include fever, swollen glands, painful ulcers in the mouth. After a few years, other symptoms start, including: diarrhea, weight loss, and increased number of infections Common infectious diseases caused by parasites Malaria ► Malaria is caused by parasites, which are spread to people through the bites of infected mosquitoes. It is preventable and curable. ► Symptoms include fever, headache and chills are typically experienced. Severe malaria can cause multi-organ failure in adults, while children frequently suffer from severe anaemia, respiratory distress. Preventing Infectious Diseases ► Wash your hands frequently. ► Don't share personal items. ► Cover your mouth when you cough or sneeze. ► Get vaccinated. ► Use safe cooking practices. ► Be a smart traveler. ► Don’t pick your nose (or your mouth or eyes either). ► Exercise caution with animals. ► Watch the news, and be aware of disease outbreaks. Noninfectious Diseases ► https://www.youtube.com/watch?v=fK1_SH3X2ek&t=4s Noninfectious Diseases ► Noninfectious diseases can't be passed from one person to another. Instead, these types of diseases are caused by factors such as the environment, genetics, and lifestyle. ► Examples of conditions caused by environmental or lifestyle factors include heart disease and skin cancer. We can't change our genetic codes, but there are plenty of ways to prevent other noninfectious diseases. For example, cutting down on exposure to cigarette smoke and the sun's rays will prevent certain types of cancer. ► chronic noninfectious diseases can be prevented. The chronic noninfectious diseases that cause the most deaths in many developed countries are largely preventable. These diseases are heart disease, stroke, diabetes and cancer, and though they do have some genetic components, they also have many lifestyle components. ► A healthy lifestyle can help reduce your risk of developing many noninfectious diseases. ► You can lower your risk of cancer by avoiding habits that expose you to carcinogens, such as smoking and tanning beds.
