IMM2022 Vaccination Vocabulary Flashcards

A set of vocabulary-style flashcards covering key vaccination concepts, technologies, and notable examples from the lecture notes.

Vaccination

Administration of a vaccine preparation to stimulate protection against a specific pathogen.

Immunisation

The immune response that follows vaccination or natural exposure; includes passive and active, natural and artificial forms.

Eradication

Permanent global reduction to 0 cases of a disease (e.g., smallpox, certified 1980).

Elimination

Reduction to near zero cases within a defined geographic area, with the pathogen possibly existing elsewhere.

Herd immunity

When a sufficient proportion of a population is immune, transmission chains are interrupted, protecting the unimmune.

Live attenuated vaccine

Contains a weakened, replication-competent pathogen that mimics natural infection; usually strong immunity but risk of reversion.

Inactivated (killed) vaccine

Pathogen that is non-replicative; safer in terms of reversion but often less immunogenic and may require adjuvants/doses.

Subunit / part-of-pathogen vaccine

Uses only selected antigens from a pathogen; often safer but require adjuvants to boost response.

Toxoid vaccine

Targets a toxin produced by a pathogen, rendered inactivated to induce immunity against the toxin’s effects.

Conjugate vaccine

Polysaccharide antigen linked to a protein carrier to create a T-cell dependent, high-affinity antibody response.

Viral-vector vaccine

Uses a harmless virus as a carrier to deliver antigen genes and induce immunity (e.g., Ebola VSV-based vaccine).

Nucleic-acid vaccine

DNA or RNA vaccine delivering genetic material that encodes an antigen for in vivo production.

mRNA vaccine

A nucleic-acid vaccine delivering mRNA encoding an antigen, usually via lipid nanoparticles; rapid design and strong immunity.

Lipid nanoparticles (LNP)

Delivery vehicles for mRNA vaccines; protect mRNA and help cell entry and endosomal escape.

Adjuvant

Substance added to vaccines to boost the magnitude/quality of the immune response (e.g., Alum, MF59, CpG 1018).

Correlates of protection

Immunological markers (antibody levels, T-cell responses) that predict protection, not always fully defined for every vaccine.

Primary immune response

Initial exposure to an antigen; slower, weaker response with activation of naïve B/T cells.

Secondary immune response

Faster and stronger response upon re-exposure due to memory B and T cells.

Memory B cells

Long-lived B cells that respond rapidly with high-affinity antibodies upon re-exposure.

Memory T cells

Long-lived T cells that provide quick and robust responses upon re-exposure to the antigen.

R0 (basic reproduction number)

Average number of secondary infections caused by one infected person in a fully susceptible population (high for measles, 18–20).

Measles herd immunity threshold

Estimated immune coverage needed to prevent transmission, commonly ≥95%.

MMR vaccine

Measles–Mumps–Rubella vaccine given in two doses; efficacy ~93% after 1st dose and ~97% after 2nd; common adverse events include injection-site soreness, fever, febrile seizures (≈1/3000).

Vaccine-derived poliovirus (VDPV)

Poliovirus that has reverted from the attenuated OPV strain; can cause outbreaks in under-immunised populations.

Oral Polio Vaccine (OPV)

Live-attenuated poliovirus given orally; provides mucosal immunity but carries a risk of VDPV reversion.

Inactivated Polio Vaccine (IPV)

Injected, non-replicating polio vaccine; cannot revert to virulence but offers less mucosal immunity and higher cost.

Ring vaccination

Vaccinating contacts and contacts-of-contacts around a confirmed case to contain an outbreak (used during Ebola trials).

BNT162b2 (Pfizer-BioNTech)

A leading mRNA vaccine against SARS-CoV-2; demonstrated about 95% efficacy in Phase III trials; strong humoral and cellular responses.

Efficiency vs efficacy (vaccine context)

Efficacy refers to risk reduction under trial conditions; effectiveness denotes real-world performance; both supported by data from trials and observational studies.

Cold chain

Infrastructure to keep vaccines at required temperatures from manufacture to administration; critical for stability, especially ultra-cold storage.

Virus-like particle (VLP) vaccine

VLPs mimic the structure of a virus without being infectious; used to induce strong immunity (e.g., HPV vaccine).

HPV vaccine

VLP-based vaccine protecting against cancer-causing human papillomavirus strains; illustrates non-infectious yet highly immunogenic design.