Chapter 10, infectious diseases Flashcards
What is the epidemiologic triangle?
A model illustrating the interaction of agent, host, and environment in causing disease.
What is an agent in the context of infectious diseases?
The factor (e.g., microorganism, chemical substance) that causes a disease or health problem.
What is an antigen?
A substance that induces the immune system to produce antibodies.
What is the attack rate?
A measure of the frequency of new cases of a disease in a specific population during a defined time period.
What is a bioterrorism attack?
The deliberate release of biological agents to cause harm or fear among a population.
What is a carrier?
A person or animal harboring a specific infectious agent without displaying symptoms but capable of spreading the disease.
What is case mapping?
The process of using geographic information to plot the location of disease cases.
What is a common-source epidemic?
An outbreak resulting from a group of people exposed to a common infectious agent (e.g., contaminated food or water).
What is a communicable disease?
A disease caused by infectious agents that can be transmitted from one person to another.
What is a contagious disease?
A highly transmissible communicable disease that spreads through direct contact or proximity.
What is direct transmission?
Spread of infectious agents through physical contact or droplets.
What is indirect transmission?
Spread through intermediaries, such as vectors or fomites.
What is an emerging infectious disease?
A new or previously unrecognized infectious disease that is increasing in incidence or geographic range.
What does endemic mean?
A disease or condition regularly found and consistently present in a particular region or population.
What is an enteric protozoal parasite?
Microscopic parasites that infect the gastrointestinal tract, such as Giardia or Cryptosporidium.
What is the environment in relation to infectious diseases?
External factors (physical, biological, social) that affect the spread of infectious diseases.
What is an environmental determinant?
An element in the environment (e.g., sanitation, climate) that influences disease transmission.
What is an epidemic curve?
A graph showing the number of new cases of a disease over time, often used in outbreak investigations.
What is generation time?
The time between infection in a host and the maximum communicability of the disease.
What is herd immunity?
Resistance to disease in a population due to a high proportion of individuals being immune.
What is a host?
A person or organism that provides a suitable environment for an infectious agent to live and multiply.
What is active immunity?
Protection developed through exposure to antigens or vaccination, typically long-lasting.
What is passive immunity?
Temporary immunity transferred from another source (e.g., maternal antibodies).
What is the incubation period?
The interval between exposure to an infectious agent and the appearance of symptoms.
What is an index case?
The first identified case of a disease in an outbreak.
What is infection?
The invasion and multiplication of an infectious agent in a host’s body.
What is an infectious disease?
A disease caused by infectious agents like bacteria, viruses, or parasites.
What is infectivity?
The ability of an infectious agent to establish an infection in a host.
What is isolation?
The separation of individuals with a communicable disease to prevent the spread of infection.
What is a nosocomial infection?
An infection acquired in a healthcare setting, such as a hospital.
What is a parasitic disease?
An illness caused by parasites (e.g., malaria, hookworm).
What is a point-source epidemic?
An outbreak where exposure to the infectious agent occurs at one specific location or time.
What is a portal of entry?
The site through which an infectious agent enters a host’s body.
What is a portal of exit?
The site through which an infectious agent leaves a host’s body (e.g., respiratory droplets, blood).
What is quarantine?
The restriction of movement for individuals exposed to a communicable disease to prevent its spread.
What is a reservoir?
A habitat (animal, human, or environment) in which an infectious agent lives, grows, and multiplies.
What is resistance in the context of infectious diseases?
The host’s ability to fend off infectious agents or diseases.
What is a sexually transmitted disease (STD)?
Infections spread primarily through sexual contact.
What is a subclinical (inapparent) infection?
An infection without noticeable symptoms, yet capable of spreading the disease.
What is a toxin?
A harmful substance produced by microorganisms, plants, or animals.
What is vaccination (immunization)?
The administration of a vaccine to stimulate active immunity against a specific disease.
What is a vaccine-preventable disease?
Diseases that can be effectively controlled or prevented through vaccines (e.g., measles, polio).
What is a vector?
A living organism, such as a mosquito or tick, that transmits infectious agents.
What is a vehicle in the context of infectious diseases?
A non-living intermediary (e.g., water, food) that transmits infectious agents.
What is virulence?
The severity or harmfulness of a disease caused by an infectious agent.
What is zoonosis?
A disease transmissible from animals to humans.
What is the difference between a reservoir and a vector?
Reservoir: Natural habitat of the agent.
Vector: Living carrier transmitting the agent.
