1What do vaccines protect against?
Disease
2How do vaccines work?
Trigger immune response
3What do vaccines contain?
Antigens from pathogens
4What type of pathogen is in vaccines?
Dead or attenuated (weakened)
5What do vaccines stimulate?
Memory cell production
6What does immunity prevent?
Disease symptoms
7What is herd immunity?
Protection from reduced infection spread
8What causes antigenic variation?
Changes in pathogen antigens
9What does antigenic variation affect?
Primary and secondary responses
10Why is antigenic variation a problem?
Memory cells don’t recognize new antigens
11What disease is affected by antigenic variation?
Influenza
12Why does the flu vaccine change?
Antigens of the virus change yearly
13What are the two types of immunity?
Active and passive
14What is active immunity?
Antibody production by immune system
15What does active immunity require?
Exposure to antigens
16What are the types of active immunity?
Natural and artificial
17What is natural active immunity?
Immunity from catching a disease
18What is artificial active immunity?
Immunity from vaccination
19What is passive immunity?
Antibodies provided by another source
20What does passive immunity not require?
Exposure to antigen
21What are the types of passive immunity?
Natural and artificial
22What is natural passive immunity?
Antibodies from breast milk or placenta
23What is artificial passive immunity?
Antibodies from injection (e.g., tetanus)
24How long does active immunity last?
Long-term (memory cells produced)
25How long does passive immunity last?
Short-term (antibodies broken down)
26What does the flu vaccine contain?
Inactivated virus or antigens
27Why are flu vaccines updated annually?
To match changing virus antigens