Pathogens and Immunity

How do vaccines work?

Multiple Choice

What is in a vaccine?

• Weakened or inactivated pathogens

• Alien technology
• Rainbows and unicorns
• Sugar and spice

Vaccines contain dead, weakened, or partial forms of pathogens.

**remember, pathogens are invaders that don't belong in our bodies!

What's in a vaccine?

Dr. Edward Jenner created the world's first successful vaccine. He found out that people infected with cowpox were immune to smallpox. In May 1796, English physician Edward Jenner expands on this discovery and inoculates (essentially, vaccinates) 8-year-old James Phipps with matter collected from a cowpox sore on the hand of a milkmaid. James then developed immunity to cowpox and smallpox from this!

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The first vaccine

But how does this work??

Recall how the immune system works.

​*Remember, antigens are how our bodies identify cells!

​Helper T-Cells are special cells in our immune system that can assist in communication with other cells.

1. The immune system recognizes the pathogen

2. Immune system builds up a defense against the pathogen by creating antibodies (this can take several days to do) and increasing the number of white blood cells.

3. Immune system destroys the pathogen.

4. Memory Cells are created that "remember" how to attack the pathogen if exposed again in the future!

​In Summary...

Reorder

Order the steps of how the immune system works!

• The immune system recognizes a pathogen!

• The immune system increases WBCs and starts to build antibodies.

• The immune system attacks and destroys the pathogen.

• Memory cells retain information to help attack the pathogen FASTER in the future.

1

2

3

4

• 1
• 2
• 3
• 4

The weakened, dead or partial pathogens present in a vaccine aren't able to cause disease.

BUT they do trigger an immune response - this is why you may feel some symptoms associated with sickness when you get a vaccine (sore arm, mild fever, etc.).

This is all part of your immune system working to develop a defense and MEMORY CELLS to protect you from the pathogen if exposed to it in the future.

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Vaccines activate the immune system!

Multiple Choice

How do vaccines provide immunity?

• They weaken the immune system

• They trigger the immune system to produce antibodies and create memory cells.

• They contain medicine that fights off pathogens.

• Vaccines introduce live, fully active pathogens into the body

Let's practice and review our knowledge of the immune system and vaccines!

Match

Match the following

• Marker on cell membranes used to identify cells

• Disease-causing agent

• Preventative medicine that works by tricking the immune system to learn how to fight of pathogens!

• Protection against disease

• Cell created by the immune system to help remember how to fight off pathogens

Antigen

Pathogen

Vaccine

Immunity

Memory Cell

• Antigen

• Pathogen

• Vaccine

• Immunity

• Memory Cell

Multiple Choice

What body system do vaccines trigger a response from to develop protection against pathogens?

• Immune system
• Circulatory system
• Respiratory system
• Digestive system

Multiple Choice

What do vaccines contain?

• Vaccines contain sugar only
• Weakened or inactive parts of pathogens

• Vaccines contain live, fully intact viruses

• Vaccines missing amino acids

Multiple Choice

How do vaccines provide immunity?

• Vaccines trigger the immune system to produce antibodies and memory cells that recognize and fight off pathogens.

• Vaccines provide immunity by changing the DNA of the individual
• Vaccines work by weakening the immune system
• Vaccines create a shield around the body to block pathogens