Some of the diseases are caused due to malfunctions or dysfunctions of body organs and some diseases are caused due to destructive activities of germs in our body. Most of diseases that are caused due to foreign germs and worms can transfer from a diseased person to other healthy people. Such diseases are known as communicable diseases.
Diseases
Diseases
Introduction
The term ‘diseases’ is made up of a prefix ‘dis’ and a root word ‘ease’. ‘Dis’ stands for ‘no’ and ‘ease’ means ‘comfort or easiness’. Therefore, the meaning of diseases is not to have easiness in the body.
Disease is the condition having discomfort or improper function of some of our body parts. There are various minor and major diseases occurring in our body.
Some of the diseases are caused due to malfunctions or dysfunctions of body organs and some diseases are caused due to destructive activities of germs in our body. Most of diseases that are caused due to foreign germs and worms can transfer from a diseased person to other healthy people. Such diseases are known as communicable diseases.
Cholera, malaria, scabies, conjunctivitis, tuberculosis, typhoid etc are some examples of communicable diseases. Diseases caused due to lack of nutrition or accidents are non-communicable diseases. Marasmus, kwashiorkor, rickets, scurvy, etc are non-communicable diseases.
Causative agents
The organisms which live in our body disturb the works of our organs, and cause diseases are known as causative agents. Bacteria, viruses, protozoan, worms, and mites are some of the causative agents.
Modes of transmission
The causative agents of diseases transfer from one person to another person through different means. Some of the means of transmission are air, water, food, direct contacts, indirect contacts, insects or flies. For example, tuberculosis and common cold are transferred through air, typhoid through contaminated water, scabies through direct touch and use of victim’s clothes. Some of the causative agents need help of other living things to be transferred from one person to another person. For example, plasmodium malaria, the causative agents of malaria, are transferred from one person to another person by female anopheles mosquito. Such organisms are known as vectors. Mosquito serves as the vector for communication of malaria. Similarly, dogs, flies, and lice serve as the vectors for rabies, kala-zaar, and typhoid fever respectively.
Disease cycle
The communicable diseases form a cyclic path for their communication from one person to another. The reservoir, receiver, and medium are the elements of the diseases cycle. Diseases cycle can be defined as the path joining reservoir, medium and receiver of communicable diseases in cyclic order. The cycle explains that the causative agents are taken by specific mediums and transferred to a healthy person. The healthy person becomes receiver first. The causative agents multiply and increase number and develop the receiver to reservoir. The reservoir becomes capable of transferring germs to the medium again.
Some communicable diseases
Tuberculosis: tuberculosis is a communicable diseases caused due to presence of causative agent ‘tuberculosis bacilli’. This species of bacteria are transferred through the contaminated air. If an infected person coughs or sneezes in front of others, the air around this person is contaminated with the causative agents.
Measles: measles is also known as rubeola. It is an infection of the respiratory system caused by a virus known as paramyxovirus.
Diphtheria: diphtheria is an upper respiratory tract illness caused by a bacteria corynebacterium diphtheriae. These diseases was quite common in the past but now it has largely been controlled through widespread vaccination.
Polio: poliomyelitis, often called polio or infantile paralysis, is a viral infectious disease caused due to the infection of polio virus.
Some of the diseases are caused due to malfunctions or dysfunctions of body organs and some diseases are caused due to destructive activities of germs in our body. Most of diseases that are caused due to foreign germs and worms can transfer from a diseased person to other healthy people. Such diseases are known as communicable diseases.
