Vaccination is when a virus, or bacteria, is deliberately administered to you (usually by injection) so that your immune system can prepare to fight a future infection. The best way to do this is to expose your body to killed or weakened viruses or bacteria that can’t cause infection.

Vaccinations work by boosting the immune system's ability to fight certain infections. The vaccination teaches your child's immune system to recognize and fight specific germs so that when they are exposed to them, he or she has a much lower risk of getting sick.

How do vaccines work? Do they work against viruses and bacteria?

Vaccines work to prime your immune system against future “attacks” by a particular disease. There are vaccines against both viral and bacterial pathogens, or disease-causing agents.

When a pathogen enters your body, your immune system generates antibodies to try to fight it off. Depending on the strength of your immune response and how effectively the antibodies fight off the pathogen, you may or may not get sick.

If you do fall ill, however, some of the antibodies that are created will remain in your body playing watchdog after you’re no longer sick. If you’re exposed to the same pathogen in the future, the antibodies will ”recognize” it and fight it off.



Measles is very contagious; you can get it just by being in the same room with an infected person. The risk of death from measles is highest for adults and infants.


Most people with HPV will not have any long-term effects, but some will get cancer. HPV causes 70 percent of all cervical cancers.


Tetanus causes “lockjaw” and spasms or paralysis of other muscles in the body. Adults should get Tdap once and then Td every 10 years after.