Principles of Disease and Epidemiology

Flashcards covering key concepts from the lecture on Principles of Disease and Epidemiology related to infectious diseases, microbiota, and epidemiology.

Epidemiology

The study of where and when diseases occur and how they are transmitted in populations.

CDC

Centers for Disease Control and Prevention; collects and analyzes epidemiological information in the United States.

Emerging Infectious Diseases (EIDs)

Diseases that are new, increasing in incidence, or showing a potential to increase in the near future.

Commensalism

A symbiotic relationship where one organism benefits and the other is unaffected.

Mutualism

A symbiotic relationship where both organisms benefit.

Parasitism

A symbiotic relationship where one organism benefits at the expense of the other.

Koch's Postulates

Criteria established by Robert Koch to prove that a specific microbe causes a specific disease.

Normal Microbiota

Microbes that permanently colonize the host and do not cause disease under normal conditions.

Transient Microbiota

Microbes that may be present for days, weeks, or months but do not permanently colonize the host.

Pathology

The study of disease.

Etiology

The cause of a disease.

Infection

Invasion and colonization of pathogens in the body or host.

Disease

An abnormal state in which the body is not performing normal functions.

Incidence

Number of people with new cases of disease during a specific time period.

Prevalence

Number of people with existing cases of disease, regardless of when it first appeared.

Sporadic disease

A disease that occurs only occasionally.

Endemic disease

Disease that is constantly present in a population.

Epidemic disease

Disease acquired by many people in a given area in a short time.

Pandemic disease

Worldwide epidemic affecting more than one continent.

Microbial antagonism

Competitive exclusion; competition between microbes.

Reservoir of infection

Continual source (pool) of infection.

Vector-borne transmission

Transmission of disease by a vector such as an arthropod.

Healthcare-Associated Infections (HAIs)

Infections acquired while receiving treatment in a healthcare facility.

Nosocomial infections

Another term for healthcare-associated infections.

Zoonoses

Diseases transmitted from animals to humans.

What are the 4 requirements

for Koch’s postulate?

1. The same pathogen must be present in every case of

the disease and absent from a healthy host

2. The pathogen must be isolated from the diseased host

and grown in pure culture.

3. ’The pathogen from the pure culture must cause the

disease when its inoculated into a healthy, susceptible

laboratory animal.

4. The pathogen must be isolated from the inoculated

animal and must be shown to be the original organism

Name one exception.

Exceptions to Kochs

postulates

 Some pathogens can

cause several disease

conditions

 Some diseases don’t

have symptoms

 Some pathogens

cause disease only in

humans

 Some microbes have

never been cultured

Symptoms

changes in body function that are felt by a patient as a result of
disease (e.g. body pain)