Disease and its types

Disease is a condition in which a person does not feel mentally and physically active, good, and healthy. Diseases may also refer to the malfunctioning of any particular organ of a person.

There are two types of disease based on their causes.

• Viral disease
• Bacterial disease

Bacterial diseases are those diseases which are caused by Bactria and its activity in the body of a patient, while viral disease are caused by the activity of some virus in the body of a patient.

Viral Diseases

The word virus means poison. Viruses are the tiniest and simplest living organisms. They are non-cellular parasites who are non-living outside the host cell. To live and reproduce they need a body of host. When virus enters into the host cell it causes different diseases in the host. It could infect and even kill the host in extreme cases. They could infect animals, plants, human beings, and bacteria as well. Those viruses which infect bacteria are known as bacteriophage.

Viral Diseases in Animals:

Virus causes many diseases in human beings and it is also involved in the development of cancer.  Following are some common viral diseases in animals:

• Poliomyelitis:

This disease is caused by polio virus. It enters the body through mouth and from alimentary canal; it is transferred in to the blood vessels. By the circulation of blood, it reaches the nervous system and affects the nerve cells. Ti causes paralysis of certain organs of the body of the host.

• Influenza:

This disease is commonly called “flue” and is caused by “myxovirus-influenzae”. It takes almost 2 to 3 days to appear after infection it enters the body of the host from nose openings. It can cause severe weakness in the body and sometime may result in pneumonia.

• Hepatitis A, B, C, D, E

This disease is caused by hepatitis virus A, B, C, D, E respectively. The sources of transmission of these viruses are infected water or food, blood transfusion, sexual contact, sharing used hypodermic needles through cut and wound.

• AIDS

HIV virus (Human Immune Deficiency) causes Acquired Immune Deficiency Syndrome. It infects the special cell type of immune system (white blood cells) that type is CH- T Lymphocytes. AIDS is not a particular disease, it is rather a condition in which different viruses and bacterias attack the body of the host to insufficient and inactive immune system. As a result of this, the body of the host is subjected to different diseases which eventually cause the death of the host.