HMI P4

Prevalence

Number of people with a disease at any given time

Incidence

Number of NEW cases at a given time

Mortality

Number of deaths due to a disease

Sporadic disease

Few cases and then a spike then back to few

Endemic disease

A constant level of a disease

Epidemic disease

A stark increase in the amount a disease in a specific population

Pandemic disease

A stark increase in the cases of a disease all over the world

What is the purpose of Koch’s postulates

They are used to identify a microorganism that is the cause of a disease

What are Koch’s Postulates

The agent must be present in all hosts with the disease but absent in healthy hosts, The agent must be isolated from the host and grown in pure culture, The agent must cause the same disease when given to a healthy host, The agent must be re-isolated from the new host and grown in pure culture

Why are these Postulates not perfect and why can they not be applied to the identification of all infectious agents

Some organisms cannot be cultured, some organisms are opportunistic, some organisms can only infect human (Ethically cannot give it to a human)

Etiological agent

The organism that causes a certain disease

What are nosocomial diseases

An infection that is acquired in a hospital/medical office

What is a source of spread

The initial point of where a disease comes from

Common source v Propagated spread

Single source for all individuals infected v Person to persion infection, either direct or indirect

Observation vs Experimental epidemiological studies

Subjects are not manipulated vs subjects are manipulated

Communicable vs Non Communicable

Can spread from person to person through either direct or indirect contact v Disease that cannot be spread from person to person

Non-Infectious spread

Disease not caused by pathogens; genetic disorders