Vaccines 101: How vaccines work

Summary

Vaccines play a crucial role in protecting us from infectious diseases by training the immune system to recognize and attack pathogens. They activate the adaptive immune system, which generates antibodies and memory cells to fight future infections. Different vaccine types, such as live attenuated and subunit vaccines, work by introducing weakened or partial pathogens to the immune system, helping it build immunity. Vaccination also helps protect those unable to receive vaccines through herd immunity, disrupting infection chains. Successful vaccination campaigns have even led to the eradication of diseases like smallpox, showcasing the power of vaccines and herd immunity.

Takeaways

• 😀 Vaccines play a crucial role in protecting us from infectious diseases by training the immune system to detect and attack pathogens.
• 😀 The adaptive immune system is the part of the immune system that vaccines train to recognize and respond to invaders like viruses and bacteria.
• 😀 Vaccines help the immune system identify pathogens by introducing antigens, which are molecular markers found on all pathogens.
• 😀 After detecting an antigen, the adaptive immune system generates antibodies and killer T cells to fight and destroy the pathogen.
• 😀 The adaptive immune system also creates memory cells, which enable it to respond faster and more effectively if the same pathogen is encountered again.
• 😀 Immunity is the result of the immune system's ability to remember past infections and protect against future ones.
• 😀 Live attenuated vaccines, such as MMR and BCG, use weakened pathogens to trigger a strong immune response without causing disease in healthy individuals.
• 😀 Subunit or recombinant vaccines, such as the HPV vaccine, contain only parts of the pathogen and require adjuvants to help the immune system recognize and respond to them.
• 😀 Subunit vaccines are non-infectious and safe for people with weakened immune systems but may not provide as long-lasting protection as live attenuated vaccines.
• 😀 Vaccines help protect individuals and also create herd immunity, which prevents the spread of diseases within a population, benefiting those who can't be vaccinated.
• 😀 Herd immunity works by disrupting infection chains, making it harder for pathogens to spread, which can lead to the complete eradication of diseases, like smallpox.

Q & A

What role do vaccines play in protecting us from infectious diseases?

Vaccines protect us from infectious diseases by training the immune system to detect and attack pathogens, helping the body develop immunity without causing illness.

How does the immune system detect pathogens?

The immune system detects pathogens by recognizing molecular markers called antigens, which are found on the surface of all pathogens, such as bacteria and viruses.

What happens once the adaptive immune system detects an antigen?

Once the adaptive immune system detects an antigen, it starts mounting a response. B cells turn into plasma cells to produce antibodies, and immune cells called phagocytes work with antibodies to destroy the pathogen.

How do T cells contribute to fighting infections?

T cells, specifically killer T cells, detect and destroy cells infected with pathogens, playing a crucial role in eliminating infected cells from the body.

What is immunity, and how is it developed?

Immunity is the body's ability to recognize and fight pathogens it has encountered before. It is developed when the adaptive immune system creates long-lived memory cells that can quickly respond to future infections from the same pathogen.

How do vaccines work to create immunity?

Vaccines introduce antigens into the body, which trains the immune system to recognize and fight the pathogen. This process creates immunity without causing illness.

What are live attenuated vaccines, and how do they work?

Live attenuated vaccines contain a weakened version of a living pathogen that cannot cause disease in healthy individuals but still triggers a strong immune response, creating memory cells for long-term protection.

What is the difference between live attenuated vaccines and subunit vaccines?

Live attenuated vaccines contain weakened pathogens that can trigger an immune response similar to a real infection. Subunit vaccines, on the other hand, contain only parts of the pathogen, such as proteins, to stimulate the immune system.

Why are adjuvants used in subunit vaccines?

Adjuvants are used in subunit vaccines to enhance the immune response. They help activate the immune system so it can recognize and respond to the subunit antigens.

What is herd immunity, and how does it protect vulnerable individuals?

Herd immunity occurs when a large percentage of a population is immune to a disease, either through vaccination or previous infection. This reduces the spread of the disease, protecting individuals who cannot be vaccinated, such as those with weakened immune systems.