Chapter 8 Immunity - Video Lecture Flashcards

Flashcards covering the key concepts from the lecture notes on natural vs artificial immunity, active vs passive strategies, vaccines, herd immunity, pathogen identification, transmission, and emerging disease dynamics.

What is natural immunity?

Immunity that develops to a disease without any medical intervention.

What is artificial immunity?

Immunity that develops as a result of a medical intervention (e.g., vaccines, antisera).

What is active immunity?

Immunity produced when the body's own adaptive immune system generates antibodies and memory cells.

What is passive immunity?

Immunity created by antibodies obtained from an external source, without the body's own production of memory cells.

What is natural active immunity?

Natural exposure to a pathogen leading to an immune response with antibodies and memory cells.

What is natural passive immunity?

Antibodies transferred from mother to child (e.g., via placenta or breast milk).

What is artificial active immunity?

Immunity created through vaccination, where the body develops antibodies and memory cells without illness.

What is artificial passive immunity?

Immunity provided by preformed antibodies from an external source, without generating memory cells.

What is herd immunity?

Population-level immunity that reduces pathogen spread and protects those who are not immune.

What is a vaccine?

A medical treatment containing antigens that stimulates the adaptive immune system to create immunity without causing disease.

What is a primary immune response?

The initial adaptive immune response to a first exposure to an antigen; slower with moderate antibody production and memory formation.

What is a secondary immune response?

A faster, larger antibody response upon re-exposure due to existing memory cells.

What are memory cells?

Long-lived B and T cells that respond rapidly to subsequent exposures to the same antigen.

What is a booster vaccine?

An additional vaccination given after the initial series to re-stimulate memory cells and increase immunity.

What is tetanus and what causes it?

A disease caused by Clostridium tetani toxin (tetanospasmin) that disrupts nervous system function, leading to muscle spasms.

How many doses are typically required for artificial active immunity to tetanospasmin in Australia?

Six vaccinations from age 2 months to 12 years.

What are the five modes of transmission used to spread pathogens?

Airborne, droplet, direct physical contact, indirect physical contact (fomites/vector), and faecal-oral.

What is ELISA used for in pathogen identification?

A serology-based test to detect antibodies or antigens in a serum sample.

What does R0 (basic reproduction number) indicate?

The expected number of secondary cases produced by one infected individual in a completely susceptible population.

What does CFR (case fatality rate) measure?

The proportion of deaths among diagnosed cases of a disease.

What is an emerging disease?

A disease that is new to humans or increasing rapidly in incidence and not previously recognized.

What is a re-emerging disease?

A disease that was once a major problem but has reappeared or increased in incidence.

What does endemic mean?

A disease that is consistently present at a baseline level in a population.

What is an epidemic?

A dramatic increase in disease occurrence in a specific population at a specific time.

What is a pandemic?

An epidemic that spreads across countries or continents.

Who was John Snow and why is he important in epidemiology?

A physician who traced a cholera outbreak to contaminated water, laying the foundation for modern epidemiology.

What is quarantine?

Separating and restricting movement of ill or potentially ill individuals to prevent disease spread.

What is antimicrobial resistance (AMR)?

The ability of microorganisms to survive exposure to antimicrobial drugs, often due to misuse or overuse.

Why are vaccines a central part of herd immunity and disease control?

Vaccines stimulate adaptive immunity, increasing the immune proportion of a population and reducing transmission to susceptible individuals.