Reference

Glossary of immunisation terms

The acronyms and clinical words you’ll see across this site, defined in plain English. Drawn from the Australian Immunisation Handbook, ATAGI advice statements, and the Department of Health and Aged Care.

ACCHO: An Aboriginal Community Controlled Health Organisation (ACCHO) is a primary health care service initiated, governed and operated by the local Aboriginal community to deliver holistic, comprehensive and culturally safe health care. ACCHOs are members of NACCHO at the national level and of VACCHO in Victoria. Many ACCHOs provide vaccinations, including all NIP-funded vaccines and additional vaccines for which Aboriginal and Torres Strait Islander peoples are eligible from younger ages. We are happy to refer or share records with an ACCHO at your request.
adjuvant: An adjuvant is a substance added to some vaccines to enhance and prolong the immune response to the antigen. Aluminium salts have been used safely for nearly a century in many routine vaccines; newer adjuvants such as AS01, MF59 and CpG 1018 are used in shingles, enhanced influenza and hepatitis B vaccines respectively. Adjuvants are particularly valuable for older adults, whose immune systems can be less responsive without one, which is why the enhanced influenza vaccine for over-65s is adjuvanted.
AHPRA: The Australian Health Practitioner Regulation Agency (AHPRA) operates the national registration and accreditation scheme for 16 health professions in partnership with each national board. The Pharmacy Board of Australia, supported by AHPRA, sets the standards pharmacist immunisers must meet, including initial training, ongoing CPD, anaphylaxis management and adherence to the Australian Immunisation Handbook. All immunisers at Immunisation Hub hold current AHPRA registration with an immunisation endorsement notation under Victorian scope of practice.
AIR: The Australian Immunisation Register (AIR) is a national register that records vaccinations given to people of all ages in Australia. Recognised immunisation providers, including pharmacist immunisers, are legally required to report every vaccination to AIR, ordinarily within 24 hours and no later than 10 working days. Individuals can view their complete AIR history at any time through their myGov account linked to Medicare, or via the Medicare Express Plus mobile app. Printed immunisation history statements can also be requested for school enrolment, employment or travel.
antigen: An antigen is anything the immune system identifies as foreign and reacts to. Vaccines work by exposing the immune system to a safe form of an antigen, for example a killed virus, a weakened virus, a single bacterial protein, or the genetic instructions for a single protein (as with mRNA vaccines). Because the vaccine antigen cannot cause disease, your immune system can learn to recognise it and develop antibodies and memory cells without you having to get sick first. The next time you encounter the real pathogen, your immune system responds faster and more effectively.
ATAGI: The Australian Technical Advisory Group on Immunisation (ATAGI) is a clinical and scientific advisory body to the Minister for Health and Aged Care. ATAGI reviews evidence on vaccine safety, effectiveness and epidemiology, and issues recommendations that shape the Australian Immunisation Handbook and the National Immunisation Program schedule. ATAGI advice statements are typically the first place clinicians look when eligibility, dose intervals, or new boosters change.
Australian Immunisation Handbook: The Australian Immunisation Handbook is the authoritative clinical reference for the use of vaccines in Australia. Published online by the Department of Health and Aged Care and continuously updated on ATAGI advice, the Handbook covers vaccine descriptions, recommendations, contraindications, precautions, dose intervals, catch-up schedules, and the procedures immunisers must follow before, during and after vaccination (including the 15-minute observation period and management of immediate adverse events).
Catch-up schedule: A catch-up schedule is a personalised vaccination plan for someone whose record is incomplete, for example new arrivals to Australia, adolescents who missed a school dose, or adults without two documented MMR doses. The Handbook publishes minimum dose intervals and age caps that the immuniser uses to build the safest, fastest sequence. NIP-funded catch-up applies to people aged under 20, and to refugees and humanitarian entrants of any age; other catch-ups may be funded under state programs or self-funded.
cold chain: Vaccines are biological products that lose potency if they get too warm or too cold. The cold chain is the system of refrigerated storage, transport and monitoring that keeps every dose between +2°C and +8°C (with some products requiring frozen or ultra-cold storage) from manufacture to administration. Immunisation Hub follows the Strive for 5 national cold chain guidelines, including dedicated vaccine refrigerators with continuous temperature logging, twice-daily checks, and documented cold chain breach procedures.
contraindication: A contraindication is a clinical reason a vaccine should not be given to a particular person. The Australian Immunisation Handbook recognises only two absolute contraindications that apply to every vaccine: (1) anaphylaxis after a previous dose of the same vaccine, and (2) anaphylaxis after exposure to any component of the vaccine. Most other situations, mild illness, allergies that are not anaphylactic, immunosuppression, are precautions rather than contraindications and are worked through during the pre-vaccination screening checklist with your immuniser.
herd immunity: Herd immunity, also called community immunity, is the indirect protection from infectious disease that happens when a sufficiently high proportion of a population is immune, through vaccination or prior infection. Once the proportion of immune people exceeds the threshold needed to interrupt transmission, the pathogen can no longer find enough susceptible hosts to keep spreading. The threshold depends on how contagious the pathogen is, measles needs roughly 95%, while polio needs around 80%. Herd immunity matters because some people cannot be vaccinated (infants under the minimum age, people on certain immunosuppressive therapies, people with severe allergies to a vaccine component), and they rely on those around them being immune.
inactivated vaccine: Inactivated vaccines contain pathogens that have been killed by heat, chemicals or radiation, or only specific pieces of the pathogen (subunit, recombinant, polysaccharide or conjugate vaccines). They cannot replicate in the body and cannot cause the disease. Examples include the seasonal influenza vaccine, hepatitis A, the inactivated polio vaccine (IPV) used in DTPa-IPV combinations, and most modern shingles and HPV vaccines. Inactivated vaccines often require multiple doses and may include an adjuvant to maintain a strong, durable response.
live vaccine: Live attenuated vaccines use a virus or bacterium that has been weakened in the laboratory so it can still trigger a strong immune response but cannot cause the disease in healthy people. Examples include MMR, MMRV (measles-mumps-rubella-varicella), rotavirus, BCG, yellow fever, and the older live-attenuated zoster (shingles) vaccine that the National Immunisation Program previously used. Live vaccines are usually not given during pregnancy or to people with severe immunosuppression; non-live alternatives exist for many of these — for example, the recombinant shingles vaccine now used under the NIP is non-live and suitable for immunocompromised adults.
mRNA vaccine: Messenger RNA (mRNA) vaccines deliver a short, lab-made strand of genetic code, wrapped in a lipid nanoparticle, that instructs your cells to make a single, harmless viral protein (for the COVID-19 vaccines, the SARS-CoV-2 spike protein). The mRNA itself never enters the cell nucleus and is broken down within days; the protein it briefly produces is what triggers the immune response. mRNA vaccines were the first new vaccine platform to be approved in over 20 years and have since been authorised for COVID-19 in Australia and are under active development for influenza, RSV and other targets.
NIP: The National Immunisation Program (NIP) provides free vaccines to people of all ages who meet the eligibility criteria, including infants, children, adolescents, pregnant people, adults at higher risk, older Australians, and Aboriginal and Torres Strait Islander peoples. Vaccines are added or updated on advice from ATAGI. The NIP schedule sits inside, and is interpreted via, the Australian Immunisation Handbook. State and territory health departments may also fund additional vaccines on top of the NIP (for example, the Victorian MMR catch-up for adults aged 20–59).
pharmacist immuniser: A pharmacist immuniser is a registered pharmacist who has completed an accredited immunisation training program and meets the Pharmacy Board of Australia and AHPRA requirements to administer vaccines, including anaphylaxis management and CPR. In Victoria, pharmacist immunisers can vaccinate people aged 5 and over with a defined list of vaccines under the Drugs, Poisons and Controlled Substances Regulations. Scope is reviewed by the Victorian Department of Health and expands as evidence and training pathways evolve.
SAFEVAC: SAFEVAC (formerly SAEFVIC) is the Victorian state-funded service for reporting and following up adverse events after vaccination. It sits within the Murdoch Children’s Research Institute and works closely with the TGA. Both clinicians and members of the public can report. Reports help refine national vaccine safety advice. If you have an unusual reaction after a vaccine we give, we can help you submit a SAFEVAC report and, where indicated, arrange specialist review through their clinic. The reporting line is 1300 882 924 (option 1).
TGA: The Therapeutic Goods Administration (TGA) regulates the supply, import, export, manufacturing and advertising of therapeutic goods in Australia, including all vaccines. Before any vaccine can be administered in Australia, the TGA must register it on the Australian Register of Therapeutic Goods (ARTG) after assessing its quality, safety and efficacy. The TGA also monitors vaccine safety post-market through the Database of Adverse Event Notifications (DAEN) and works with state services such as SAEFVIC.
TIS National: TIS National (Translating and Interpreting Service) is a federally funded interpreter service available 24/7 in more than 150 languages. For health appointments at registered providers, TIS is free to the patient. At Immunisation Hub we can connect to a TIS interpreter on the phone during your consult, or arrange a pre-booked interpreter for a planned visit. Call 131 450 from anywhere in Australia.

Definitions reviewed against the Australian Immunisation Handbook on 14 May 2026. We update entries as ATAGI and the Department of Health and Aged Care publish new advice. Spot something out of date? Tell us.