Disease is any process that disrupts the normal functioning of the body. In other words, any disorder in the physical, physiological, psychological or social condition of a person which is caused by nutritional deficiency, physiological disorder, genetic disorder, pathogen or any other cause can be considered as a disease.
Classification of human diseases
Congenital diseases (present from birth), Acquired diseases (develop after birth), Infectious diseases (spread from an infected person), Non-infectious diseases (do not spread from a sick person to a healthy person), The two main types of diseases are degenerative deficiencies, allergies, cancer and other diseases.
A. Congenital disease: A condition that begins at birth (such as heart defects in infants). They are caused by genetic defects, metabolic disorders or organ malfunction.
B. Acquired disease: Disease that can affect a person at any time in his or her life after birth.
The following categories generally apply to acquired diseases:
(i) Diseases spread by germs: Diseases spread from sick people to healthy people, such as measles.
ii) Degenerative conditions: Diseases that occur when some vital organs of the body stop functioning, such as heart attack.
iii)Deficiency diseases: These are caused by inadequate intake of nutrients such as minerals or vitamins, such as anemia (Fe) and beri-beri (vitamin B). In the previous lesson, you read about such diseases.
(iv) Leukemia: It is the unintentional, abnormal and unwanted expansion of cells. like breast cancer
There are two categories of acquired diseases that are studied:
i) Diseases that can spread from an infected person to a healthy person.
ii) Diseases that cannot spread further: Affected people do not spread these diseases to healthy people.
1. Diseases that can be spread by a variety of biological agents or pathogens, including helminths (worms), viruses, bacteria, and protozoa.
2. Transmission occurs through contact, water, air, food and other means.
3. Being linked to community health, diseases are a matter of concern to society.
Diseases that are not contagious and are caused by a specific factor, such as failure of a vital organ or nutrient deficiency. Avoid contact with other people to avoid spreading the disease. Ways in which infectious diseases spread Infectious diseases spread from an infected person to a healthy person in the following ways. This disease affects only one person.
Direct transmission
Pathogens of a disease infect a healthy person directly without the need for an intermediary. This can happen in several ways, including
(i) Direct contact between an infected person and a healthy person: smallpox, chickenpox, syphilis and gonorrhea are all spread through direct contact.
(ii) Droplet infection: When infected, the person coughs, sneezes or spits small droplets of mucus. Germs may be present in these droplets. A healthy person can get the infection by breathing air filled with droplets. Droplet infection spreads diseases such as the common cold, pneumonia, influenza, measles, tuberculosis and whooping cough.
(iii) Exposure to soil that contains bacteria and viruses that can cause disease. Health
(iv) Animal bite: Rabies is transmitted through injuries caused by bites from uncontrolled animals, especially dogs. The saliva of rabid animals contains the virus.
Indirect Transmission
The germs of some diseases reach the human body through some middle level experts. This can happen in several ways, including the following:
(i) Through vectors like cockroaches, houseflies and mosquitoes. Example: House flies contaminate food and beverages by carrying cholera-causing organisms on their legs and mouthparts from the feces and spit of infected individuals. A healthy person becomes victim of infection by consuming this contaminated food. Similarly, malaria parasites and dengue viruses are carried by mosquitoes.
(ii) Airborne: Pathogens can infect humans through dust and air. Epidemic typhus is spread by inhaling dried fly feces.
iii) Objects carrying infectious diseases: Clothing, utensils, toys, door handles, taps, syringes and surgical instruments are among the objects that can carry infectious diseases. iv) By inhalation: A healthy person drinks potable water (drinking water) if it is contaminated with pathogens causing diseases like cholera, diarrhea, hepatitis or jaundice.
Important terms to keep in mind
1. Pathogen: A disease-causing organism that is a living thing.
2. Species: An organism that depends on its host for food and shelter.
3. Host: The living thing on or within which the disease-causing organism hides.
4. Epidemic: Presence of large numbers of parasitic organisms on the clothing or body surface of the host.
5. A vector: This is an organism that can transmit a disease to another person by harboring a pathogen (for example, mosquitoes transmit malaria parasites to humans).
6. Carrier: This is an organism that not only physically transmits the disease to another person but also does not carry the pathogen (the housefly is a carrier of cholera germs).
7. Reservoir: An organism that is infected with many pathogens that do not harm it in any way.
8. Epidemic: The spread of a disease that kills many people in one place over a long period of time, such as plague.
9. Interleukin-6: A type of protein that works to prevent the same virus from reproducing when it attacks infected cells in the body.
10. Vaccination: Injection of a weakened strain of a particular bacteria (vaccine) to produce immunity against a disease. This is also known as vaccination.
11. Incubation time: The time between when the pathogen enters a healthy body and when symptoms of the disease appear.
12. Findings: specific morphological or physiological manifestations on the diseased organism that aid in identification of the disease.
