Why do vaccines make you sick?

Answer 1

Vaccines are not the disease itself. They make the body think that it is being attacked and it responds by making antibodies against that virus or bacteria. You can have some side effects where you may not feel well. These feeling is also a way the body fights diseases off. You know how you feel with cold infecting you. Part of that is the response you body makes when it is infected. A cold, flu, some other infection often have the same feelings (symptoms).

Answer 2

Most all medications can affect each individual in various ways, vaccines are no different. Vaccines evoke an immune system response by introduction of the culprit organism to your body through the vaccination.

Some people have a stronger immune system with a stronger response to the antigen (pathogen) in the vaccine and that can result in an "over reaction" to the vaccine which produces some of the symptoms that they feel. In other people, the immune response is not strong enough.

For example, with the flu vaccines, people with immature, malfunctioning or suppressed immune systems, if given an LAIV (live attenuated influenza vaccine), may not be able to get an immune response and antibody production quickly enough to stop a few viruses from attaching to and reproducing in their cells. As the flu virus in the LAIV does this and cells are infected, they will be split open by the viruses and release the new virus particles. The cells die causing the symptoms.

Most times if there is a reaction to the vaccine that causes symptoms of illness, these symptoms last only a day, or up to three days, before the immune system is victorious in the battle with the weakened or dead organism in the vaccine and abates the mild symptoms. Symptoms can include such things as local injection site swelling, tenderness and redness or systemic symptoms such as fatigue, mild fever, headaches and/or body aches.

Answer 3

You're not being injected with the bad stuff.

The stuff in vaccines:

-If a live vaccine - the ability of bacteria to do evil has been 'bred out', so it's generally harmless. It's also being injected into an arm, rather than a site of the body that the disease likes to hang out in, so it's even weaker in effect and your immune system can easily overpower it.

-If a protein vaccine - you're not being given the bad stuff, you're only being given chunks of the bad stuff. Like showing a photo to someone, instead of introducing them in person.

Answer 4

Vaccines use a very weakened form of a virus that isn't potent enough to attack your systems but does function to make your body produce antibodies.

Answer 5

The vaccine contains dead or weakened virus material. It is dead or too weak to hurt you, so you don't get sick.

Answer 6

Disease does not come after vaccination. You get immunity against the microorganism. That protects you from getting the disease.