Fundamentals of Microbiology

5.3.2 Diseases Classification

Endemic disease – A disease that maintain a steady, low level frequency at a moderately regular interval – also in a particular geographical location

Epidemic - A sudden increase in the occurrence of a disease over a wide segment of a population and geographic location.

Pandemic - Increase in disease occurrence within a large population over a very wide regions (world-wide)

Epidemiology - Is the Science that deals with the occurrence, determinants, distribution and control of health and disease in a defined human population

Zoonoses - Animal diseases that can be transmitted to humans

Nosocomial infections – are those caused by infectious pathogens that develop within a hospital and are acquired by patients, visitors & others while they are in hospitals.

Types of Disease

Acute disease – A disease is characterized as acute, if it develops rapidly and runs its course quickly

Chronic - Chronic diseases develop more slowly, usually less severe, persist for a long time

Patterns of disease

Signs and symptoms: When a disease occur, it is characterized by a specific set of signs and symptoms

A sign – is a characteristic of a disease that can be externally observed by examining a patient (fever, vomiting, diarrhea, cough etc.

A symptom - is a characteristic that can be observed or felt only by a patient (Nausea, weakness, paid)

The stages of a disease or disease process can be divided into

i. - Incubation - period after the pathogens entry and before any signs or symptoms appear

ii. Prodromal stage – Onset of symptoms mark the start of this stage

iii. Period of illness – It is called acute phase, where patent is ill to affect his normal functioning (This can lead to recovery or death)

iv. Period of decline – Signs and symptoms begin to disappear convalescence progress to a carrier state or freedom from pathogens

v. Full recovery – End of a disease syndrome.