# Vaccines **Vaccination** provides the human immune system with the *experience* they need to make a *strong response* but with *very little risk* to health and life. | Method | Source | Description | | ---- | ---- | ---- | | Active | Natural | When an individual’s immune system contacts an antigen that causes an infection. | | Active | Artificial | vaccination nation baby lets goooo | | Passive | Natural | Transfer of [[antibodies]] from mother to child (through the placenta or breastfeeding) | | Passive | Artificial | When antibodies or lymphocytes produced by one host are introduced into another | There are several different ways an antigen can be prepared for a vaccine: 1. *Killed Microorganisms* 2. *Attenuated Microorganisms* (Living yet weakened/virulence factors removed) 3. Genetically Engineered Organisms (or their products) 4. *Toxoids* (Inactivated Bacterial Toxins) --- An **adjuvent** is any nontoxic material that either assists in the processing of antigens by antigen-presenting cells (APCs) or nonspecifically stimulates the immune response to the antigen. - Antigens in vaccines can be mixed with these to *promote a more efficient immune response*. > [!NOTE]- The History of Vaccines > > The origins of immunology can be traced back to historical observations recognizing that people who survived an epidemic were often untouched when faced with the same disease later in life. > > The precursor to modern vaccines was **variolation**, a technique where the dried crust of smallpox pustules would be inhaled or spread over an open wound to **induce immunity**. > > The first vaccine was > > **Variolation**, the spreading of dried crust from smallpox pustules was the precursor to modern vaccines > - It is referred to as *variolation* as the smallpox disease is caused by a pathogen called *Variola* > > > **Variolation** is the technique of scraping > - Traced back to the 15th century from Chinese and Turks > > **Inoculation** is the act of inducing immunity of > ## The "Gold Standard" of Vaccination Many