Summary
Active immunity is made by your own response; passive immunity is received as ready-made antibodies.
In depth
Active natural: infection. Active artificial: vaccination. Passive natural: maternal antibodies via placenta and milk. Passive artificial: antiserum or antivenom. Passive immunity is immediate but temporary.
Passive immunity gives immediate help but no memory. Immune globulins treat tetanus, rabies and hepatitis exposures. Monoclonals are a modern form.
Common mistake: breast milk antibodies give passive, not active, immunity.
Passive immunity gives immediate but short-lived protection because there is no memory. Antivenoms, rabies immunoglobulin after exposure, tetanus immunoglobulin and monoclonal antibodies for RSV and COVID-19 are examples. Maternal antibodies protect the newborn for around 3 to 6 months, and breastfeeding adds IgA to the gut.
Active immunity takes weeks to develop but can last years or a lifetime. Combining passive and active is sometimes used: in rabies post-exposure treatment, immunoglobulin gives immediate cover while the vaccine builds long-term protection. Hepatitis B immunoglobulin and vaccine are given to babies of infected mothers.
Frequently asked questions
What is Active and Passive Immunity?
Active immunity is made by your own response; passive immunity is received as ready-made antibodies.
Which area of biology covers Active and Passive Immunity, and how advanced is it?
Active and Passive Immunity is one of the 52 topics in Immunology & Disease. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Adaptive Immunity, Antibody Classes, Primary and Secondary Response.
Why does Active and Passive Immunity matter?
Choosing the right approach depends on how fast protection is needed and for how long.
Can you give an example of Active and Passive Immunity?
Rabies post-exposure includes immunoglobulin plus vaccine.
What should I learn before Active and Passive Immunity?
Work through the Beginner topics in Immunology & Disease first, such as Immune System, Viruses, Innate Immunity, then return to Active and Passive Immunity. Intermediate topics assume the Beginner vocabulary.
What topics are related to Active and Passive Immunity?
The closest topics to Active and Passive Immunity are Adaptive Immunity, Antibody Classes, Primary and Secondary Response, Clonal Selection. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Active and Passive Immunity?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Active and Passive Immunity. To practise the whole of Immunology & Disease, use the Immunology & Disease quiz.
How is Active and Passive Immunity different from Adaptive Immunity?
Active and Passive Immunity: Active immunity is made by your own response; passive immunity is received as ready-made antibodies. Adaptive Immunity: Slower, specific defence involving lymphocytes that remember pathogens. Read both side by side and note what each one explains.
What is a common mistake about Active and Passive Immunity?
Breast milk antibodies give passive, not active, immunity.
How should I study Active and Passive Immunity step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Adaptive Immunity and explain the difference aloud. Finally, take the Immunology & Disease quiz and come back to this page for any question you miss.