Having an illness means an alteration in physiology from the normal well being of an individual or animal.
This illness can be due to a disease or a disorder.
The word “Disease” comes from the words Des+ease =lack of ease or inconvenience.
The disease can be due to is a disturbance in health conditions either infection of abnormal physiology.
The infection is one that is caused by a foreign agent leading physiological alteration.
While those of internal origin (non-infectious) can be due to some disorder of organ.
The infection is caused by microbes like bacteria, protozoa, fungi, yeast, and virus.
The non-infectious disease is caused by the derailment of physiology in some organs or even the whole body.
An infection can cause disease but not all diseases are infections.
Difference between Disease and Infection
|Sl. No||Infection||Noninfectious Disease (normal disease)|
|1||Infection is caused by a microbe or an external agent.||The disease is caused by a change in body physiology or biochemistry.|
|2.||Diagnosis shows the involvement of external or foreign agents in the sample||Diagnosis shows no foreign agents but increases or decreased levels of body biological substances like certain enzymes, hormones, ions, glucose, etc.|
|3||There is organ damage as long as the infectious agent stays in the body||There might not be organ damage if simple headache or vomiting. But if it is a chronic type there is organ damage like in diabetes and cancer.|
|3.||An infection can be prevented by vaccination beforehand.||No vaccination can work. But proper health care, lack of stress, and physical exercises can prevent disease.|
|4.||An infection is contagious, i.e. it spreads from one individual to another by means of some medium like water, air, or by a vector i.e. mosquito, rats, etc. Also, it spread from one region to another in the same body.||It does not spread from one person to another. But can spread within the person.|
|5.||Infectious disease is curable by eradication of the infectious agents. But the damage might remain.||Curable if simple and treatable if chronic type. The treatment goes on until life ends.|
|6.||The sickness lasts for a short span||It can be of a short span, repetitive with frequent recurrences or chronic based. It can subside quickly or slowly and even last for years.|
|7.||Drugs are aimed to kill infectious agents. They are called chemotherapeutic agents or antibiotics if used against bacteria.||Drugs aim to minimize the symptoms. Change in body biochemical alterations. Or replenish the lacking substance. Ex. Insulin is given to replenish the lack of production in the body.|
|8.||Relatively inexpensive. The medication for most cases is of short duration like not more than a month. Except for TB and teniasis which last for a few months.||Inexpensive if simple type. But it can be expensive and sometimes very expensive based on the condition. Also the medication will be given on a daily basis for many years or decades.|
|9||Symptoms will be debilitating due to infection. They will be clearly visible within a few hours or days of infection.||The symptoms will not be recognizable in the first weeks or months. Less debilitating in initial stages|
|10||Chances of relapse are present. I.e. the infection eliminated can return back. Hence we see secondary treatment for TB, malaria, etc. If relapsed the disease can be resistant to drugs.||No chances of relapse if cured. However, for longstanding ones, there is no definite cure.|
|11||Chances of drug resistance by the microbe.||Chances of insensitivity to drugs. The dose might be increased.|
|11.||Examples of infectious diseases cholera, TB, plague, AIDS.||Headache, pains, diabetes, heart attack, etc.|
Infection is always created by an external agent which is a microbe. But those infections with the macro-organisms are called infestations. These infestations include threadworm, Ascaris, tenia-solium, etc. These are the ones that enter the body by contaminated food or by mosquito etc. Once they enter the body grows big to few centimeters and even meters long. They keep surviving by consuming the nutrition from the body of the host. So they are called parasites.