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Why do we fall ill- Introduction
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Megha Suresh
Currently pursuing my engineeering in Biotechnology, in B.M.S college of Engineering. Dancing & Reading keeps me alive.

Unacademy user
very good..keep it up sir

  2. INTRODUCTION The condition of body to function physically, socially and mentally well is called its health o A body with good physical and mental condition we call it a healthy body. It is not just a body free from disease or weakness but a state of thorough physical, mental and social well-being o A particular abnormal condition or function affecting the part or the entire organism is called a disease o A body infected with a disease is called a diseased body.

  3. CAUSES OF DISEASES Diseases are caused as result of following reasons: - Lack of nutritious and sufficient food. Unhealthy and dirty surroundings. * Contact with an infected person. e Using the personal belongings of an infected person. o Eating untreated water and food from an unclean and unhygienic place. o Lack of hygienic practices.

  4. ACUTE DISEASE The diseases that persist for only a short period of time are called acute diseases. For example, cough, cold, fever, eto. o As acute diseases lasts for a short period of time it doesnot get enough time to cause any fatal effects to the general health.

  5. CHRONIC DISEASE The diseases that persist for a longer period of time or even lifetime are called chronic diseases. For example elephantiasis, cholesterol, heart attack, cancer, emphysema bronchitis . Fig. Elephantiasis Due to its longevity chronic diseases imparts major effects on the general heath of a person suffering from chronic disease.

  6. INFECTIOUS DISEASE o The diseases caused due to the infections spread by microbes such as bacteria, virus, fungi, etc. are called infectious diseases. For example, chicken pox, AIDS, dengue, fever, cold are caused by virus. 9 Typhoid, cholera, tuberculosis are caused by bacteria. Malaria, kala azar are caused by protozoa. These diseases are spread by the microbes. Fig. Chicken Pox They can be transferred from an infected person to a healthy by several means. Therefore, infectious diseases are also called communicable diseases.

  7. NON INFECTIOUS DISEASE The diseases that are caused by the means other than microbes are called non-infectious diseases. They are mainly caused by internal means like personal hygiene, environmental factors, genetic disorder, etc. For example, cancer, diabetes, heart disease, stroke, chronic lung disease, etc. o As they are not caused by microbes therefore they do not spread from an infected person to a healthy person through any means. Therefore, they are also called non-communicable diseases. heart attack

  8. MODES OF TRANSMISSION The diseases that spreads from an infected person to a healthy and disease free 9 These diseases spreads when an infected person sneezes or coughs, they throw o A healthy person standing nearby when inhale the air they take in the infected air Some example of communicable diseases are chicken pox, tuberculosis, o These diseases also spreads when the excreta of an infected person somehow person are called communicable diseases. tiny droplets of water into the air that contains the microbes of the infection. and may fall sick. Pneumonia, etc. gets mixed with drinking water used by other people to drink.

  9. e Diseases like cholera, typhoid spreads through this means and cause disease to a new host. o Communicable diseases also spread through sexual intercourse between an infected person and a healthy person. Therefore, diseases like Acquired Immune Deficiency Syndrome (HIV/AIDS), syphilis are sexually transmitted diseases (STDs) Acquired Immune Deficiency Syndrome (HIV/AIDS) can also spread through other means like blood-to-blood contact with an infected person by using same syringes in hospitals, or using same personal belongings (for example, razor, toothbrush, etc.).

  10. Acquired immune deficiency syndrome (HIV/AIDS) can also spread to a healthy baby from their mother during pregnancy or by breast feeding. o Some diseases like skin infections, ringworm, conjuvitis are spread by direct contact with infected person through handshakes, touch or kiss. o Many diseases are carried from an infected person to a healthy person through animals. Such animals are called vectors. Mosquitoes and houseflies are good examples of such vectors. spreads Dengue. The female anopheles mosquito spreads Malaria whereas Female Aedes mosquito Houseflies sits on garbage, drains, human and animal excreta and then flies off and sits on uncovered food consumed by healthy person. This way houseflues transmits the disease to the new healthy host.