Disease is any condition that may lead to discomfort, distress, health problems, or death of the affected person. There is difference between the HEALTHY and DISEASE-FREE state of a human body. Diseases can be classified into acute and chronic diseases , based on their durations. Diseases can also be classified into infectious and non-infectious, based on their Causes for diseases can be classified into immediate and contributory causes.
Infectious diseases spread through infectious agents(virus, bacteria, other micro-organisms). An infectious disease is called as a communicable disease, if it spreads from an infected person to a healthy person. Diseases caused by non infectious agent (excessive weight, genetic defects, etc.) are called Non-infectious disease Non-infectious diseases can’t be transferred from a diseased person to a healthy person.
Infectious agents(bacteria, protozoa, fungi, etc.) Parasites Contaminated food or water Direct physical contact Blood transmission Vectors/animals
The type of causal agent determines the type of treatment. But, an antibiotic meant to fight a certain microorganism can’t fight any other microorganism. For example, penicillin blocks the synthesis of the cell wall in bacteria. This antibiotic can be used effectively against a large number of different bacteria. However, it cannot be used on microorganisms such as virus.
Signs and symptoms of a disease depend on the affected tissue or organ. Common effects are of two types- local effects include swelling, pain, joint stiffness, joint pain, etc. occurring only at the place of infection. General effects include fever, chills, headache, fatigue, loss of appetite, etc. All these effects are caused due to inflammation.
Reducing the effect of a disease: the side effects/symptoms are reduced. Killing the cause of the disease: taking microbe-specific medicines can kill the causal organisms. It’s difficult to make anti-viral medicines, as viruses don’t posses any cellular machinery of their own to function.
General ways: Cover your mouth and nose while sneezing. Avoid contaminated food and water. Ensure proper a clean environment, disposal of sewage and a safe drinking water supply. Ensure availability of proper nutrition. Specific ways: This refers to defence provided by the immune system of a person. Vaccination