Fundamentals and Concepts of Epidemiology and Infectious Diseases

Vocabulary flashcards covering core epidemiological metrics, study designs, modes of pathogen transmission, and hospital infection control based on the lecture quiz.

Epidemiology

The study of the distribution and causes of diseases in populations to develop prevention and control strategies.

Communicable Disease

An infectious disease that can be transmitted directly or indirectly from one host to another.

Endemic Disease

A disease that is constantly present within a specific population, such as the common cold in the USA.

Basic Reproduction Number ($R_0$)

The average number of secondary infection cases originating from a single primary case.

Incidence

The number of new disease cases in a population over a specific period of time, indicating the risk of contracting the illness.

Mortality

The total number of deaths or the death rate within a population.

Reservoir

The natural habitat of an infectious pathogen, which can include humans, animals, or the environment.

Asymptomatic Infection

A condition where an individual carries and can spread a pathogen without showing any clinical symptoms.

Zoonotic Diseases

Diseases that exist primarily in animals and can be transmitted to humans, often causing severe illness.

Respiratory Pathogen Portal of Entry

The respiratory tract (nose and mouth) through which respiratory pathogens enter the body, rather than through the skin.

Direct Transmission

The immediate transfer of a pathogen to a portal of entry via direct contact, such as handshaking or sexual contact.

Hand Hygiene

Handwashing, considered the single most effective measure for preventing the transmission of infectious diseases.

Fomites

Inanimate objects, such as clothing or doorknobs, capable of transmitting infectious pathogens.

Biological Vector

A living organism, such as a mosquito, in which a pathogen multiplies and completes part of its life cycle.

Environmental Factors in Disease Spread

Abiotic elements including temperature, water, nutrients, light, and oxygen that influence pathogen survival and transmission.

Herd Immunity

Population-level resistance that occurs when a high proportion of individuals are immune, indirectly protecting non-vaccinated individuals.

Descriptive Epidemiological Studies

Studies that gather data on time, place, and affected individuals to identify outbreak patterns and risk factors.

Cohort Study

An epidemiological study design that follows groups of individuals with known exposures over time to analyze disease outcomes.

Experimental Studies

Epidemiological studies designed to test hypotheses and evaluate cause-and-effect relationships, such as the efficacy of medical interventions.

CDC

A national organization that gathers and publishes data on infectious diseases, supports laboratory networks, and produces publications such as the Morbidity and Mortality Weekly Report.

Neisseria gonorrhoeae

A primarily sexually transmitted pathogen that is not a typical cause of healthcare-associated infections, unlike Clostridium difficile, Candida species, and Staphylococcus aureus.

Healthcare-Associated Infection Transmission

The spread of pathogens in hospital settings through direct contact (healthcare staff) or indirect pathways (medical devices, air), often associated with invasive devices like catheters or ventilators.

HICPAC

An advisory committee that provides guidance and recommendations on infection control practices within healthcare settings.