Vaccine

Vaccine

          “Vaccines are antigens and in response,  immune system of the body

 produce specific antibodies against them”

A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism and is often made from weakened or killed forms of the microbe, its toxins or one of its surface proteins. The agent stimulates the body's immune system to recognize the agent as foreign, destroy it, and keep a record of it, so that the immune system can more easily recognize and destroy any of these microorganisms that it later encounters.

Types of Vaccines

          Usually there are two types of vaccines

1.    Live Vaccines (live  Attenuated Vaccines)

These vaccines are made up of living virus or bacteria that have been weakened (attenuated) by scientists. These vaccines are very effective, but in rare cases (such as in people with compromised immune systems), can cause infection.

2.    Killed Vaccines ( Inactivated Vaccines)

Inactivated Vaccines More stable than live vaccines, these vaccines contain disease microbes that have been killed with chemicals. Inactivated vaccines tend to stimulate a weaker immune response than live vaccines, and may require booster shots to maintain immunity.

Other types are.

·        Toxoid vaccines: 

When the cause of illness is a toxin that the virus or bacteria emits, scientists may be able to formulate a vaccine from just the deactivated toxin, rather than the whole bacteria. When the vaccine is administered, the immune system learns to fight off the toxin.

·        Conjugate Vaccines: 

Some bacteria have special coatings that hide them from the immune system. Conjugate vaccines link these coatings to an organism that an immature immune system can recognize, so it can respond and produce immunity.

·        Subunit Vaccines:

 These vaccines are made with only the parts of the microbe that stimulate the immune system. Subunit vaccines can be made by taking apart the actual microbe, or they can be made in the laboratory using genetic engineering techniques. Since these vaccines contain only parts of the microbe rather than the whole microbe, the chance of temporary reactions is even lower than with other kinds of vaccines.

 How vaccine works

      How vaccine works

                     Vaccines provide immunity that protects you from disease without the risk of the infection.  

Here's how vaccines work:

Ø  Vaccines contain a small amount of the germs or parts of the germs that cause disease.  But the germs in vaccines are either killed or weakened so they can't make you sick.

Ø  When you receive a vaccine, your body thinks the small amount of the disease germ is the disease itself, and your immune system starts creating antibodies (proteins that destroy disease germs).

Ø  The antibodies destroy the vaccine germs just as they would the disease germs (like a training 

Ø  These antibodies stay with you for a long time and remember how to fight off the germ.  If the real disease (not the vaccine) enters your body in the future, the antibodies are ready to fight it off before it has a chance to make you sick.

Ø  Often, your body remembers how to fight a germ for the rest of your life. However, sometimes you need a booster dose of a vaccine to remind your body how to fight off certain germs

Ø  It's just like... A dress rehearsal for your immune system so it is prepared for the ‘real show’ (the disease). 

Ø  Sometimes vaccines prevent one disease. Sometimes they are combined to protect you from several diseases with one shot. For example, the MMR vaccine provides protection against measles, mumps and rubella.

Ø  Most vaccines need more than one dose over time to produce full protection. That’s why it’s important to follow the immunization schedule - it gives the best protection with the fewest doses of each vaccine. 

Related Topics

Washing and Sterilization of Vaccination equipment at Farm