Principles of Infectious Disease and Epidemiology

A comprehensive set of 50 vocabulary flashcards based on key terms and concepts from the lecture on infectious diseases and epidemiology.

Pathogen

An organism that causes disease.

Epidemiology

The study of how diseases affect the health and illness of populations.

Infectious Disease

An illness caused by pathogens.

Koch’s Postulates

A series of four criteria to establish a causal relationship between a microbe and a disease.

Endemic Disease

A disease routinely found among particular geographic areas or populations.

Epidemic

A sudden increase in the number of cases of a disease above what is normally expected.

Pandemic

An epidemic that has spread across countries or continents.

Emerging Disease

A newly identified infection in a population.

Reemerging Disease

A previously controlled disease that is increasing in incidence.

Zoonotic Disease

A disease that can be transmitted from animals to humans.

Sporadic Disease

Isolated cases of infections in a particular region.

True Pathogen

A pathogen that can cause disease in a healthy host.

Opportunistic Pathogen

A microbe that only causes disease in a weakened host.

Communicable Disease

A disease that can be transmitted from one person to another.

Noncommunicable Disease

A disease that cannot be transmitted from an infected person to another individual.

Acute Disease

A disease with a rapid onset and progression.

Chronic Disease

A disease with a slower, long-term progression.

Reservoir

An animate or inanimate habitat where the pathogen is naturally found.

Source

The organism or environment from which the pathogen is transmitted.

Transmission

The method by which a pathogen is spread from one host to another.

Endogenous Source

When the pathogen comes from the host’s own body.

Exogenous Source

When the pathogen comes from an external source.

Direct Contact Transmission

When a host comes into physical contact with the source of the pathogen.

Indirect Contact Transmission

When pathogens spread without physical contact between source and host.

Biological Vector

An organism that carries a pathogen through part of its life cycle.

Mechanical Vector

An organism that carries a pathogen without being a host in its life cycle.

Incubation Period

The time between infection and the appearance of symptoms.

Prodromal Phase

The initial stage where vague symptoms appear.

Acute Phase

The stage of a disease when symptoms are fully developed.

Period of Decline

The stage where the symptoms begin to diminish.

Convalescent Period

The stage where the host recovers and eliminates the pathogen.

Healthcare-Acquired Infections (HAIs)

Infections that patients acquire while receiving treatment for medical or surgical conditions.

Public Health

The practice of protecting and improving the health of people in a community.

Morbidity

The condition of being diseased or the incidence of illness in a population.

Mortality

The state of being subject to death; the number of deaths in a given population.

Prevalence Rate

The total number of cases of a disease in a population at a specific time.

Incidence Rate

The number of new cases of a disease in a defined population during a specified period.

Descriptive Epidemiology

Epidemiology that aims to describe who, what, when, where, and how of health-related states or events.

Analytical Epidemiology

A type of epidemiology that investigates the causes of diseases by identifying and testing hypotheses.

Surveillance

The continuous and systematic collection of data about a specific disease.

Quarantine

A period of confinement away from the general population to prevent spread of disease.

Herd Immunity

Indirect protection from infectious disease that occurs when a large percentage of a population has become immune.

Noninfectious Disease

A disease that does not spread from person to person.

Public Health Strategies

Measures to maintain or improve the health of community populations.

Ethical Issues in Epidemiology

Dilemmas that arise concerning the rights of individuals in relation to the collective health of populations.

Informed Consent

The process of getting permission before conducting a healthcare intervention on a person.

Vaccination Programs

Public health initiatives that aim to administer vaccines to protect communities against diseases.

Types of indirect transmission

Airborne, vehicle, vector

Vehicle transmission

Pathogen is found on contaminated fomite (doorknobs, needles, sheets, food)

Vector transmission

Biological vector: organism has a role in the pathogen’s life cycle (mosquitos, ticks, fleas)

Mechanical vector: organisms does not have a role in pathogens life cycle (flies, rodents)

How is histoplasmosis spread

windborne (airborne)

How is Hanta virus spread

Stirred up animal droppings (airborne)

How is salmonellosis spread

Foodborne (vehicle)

How is HIV spread

contaminated needles (vehicle), sex (person to person), in utero (vertical), breastmilk (vertical)

How is cholera spread

Contaminated water (vehicle)