What are Vaccines?

Vaccines, or immunizations, are a huge reason people can lead healthy lives today. Thanks to innovations made in public health and modern medicine, vaccines have done a great job at reducing or eliminating many infectious diseases that used to cause devastating sickness in infants, children and adults.

A vaccine is a prepared stimulus (usually an inactive form of the disease) that is used to help the body’s immune system build up protection against infectious diseases. Vaccination is one of the most convenient and safest preventive care measures you can take for yourself and your children.

How do vaccines work?

Vaccines help the body fight illness. When bacteria or viruses get into the body, they can attack healthy cells and multiply. This invasion of bad germs is an infection that causes disease.

The immune system uses white blood cells to fight infections. The good white blood cells attack the bad infected cells and destroy them, leaving antigens (remnants of the infection). Some white blood cells create antibodies (protective proteins) that attach to antigens and help remove them from the body.

This process is how your body fights and recovers from illness. After the infection is removed, the immune system has learned how to recognize that specific germ and protect against the same infection if it enters the body again.

Vaccines help the body protect against certain diseases by imitating the infections. Immunizations use very small amounts of antigens to help the immune system recognize diseases and learn to fight them. Antigens include any substance that causes the body’s immune system to respond and go to work fighting the virus.

Many vaccines are recommended for children during their younger years as preventative care. As people get older, the protection from some vaccines that were given as a child will begin to wear off. You may also be at more risk for diseases due to your job, your environment, your lifestyle or other health conditions. Getting additional recommended vaccines as an adult helps provide continuing protection from diseases that can cause you to becoming seriously ill or hospitalized.

What are the benefits of vaccines?

Vaccines are the safest way to protect against certain diseases. Vaccines help the body build immunity to diseases without a person having to be sick first to get the immune boost. This is the best situation possible because natural illness from some diseases that are vaccine-preventable can be deadly or cause serious long-term complications.

This is even true for diseases that are known for being milder in most cases, like chickenpox or influenza. While most people do not have serious complications from these illnesses, some people may experience more severe symptoms and serious long-term effects. It’s impossible to predict how any disease will affect an individual person.

Vaccines lower your chance of getting certain diseases by helping your body safely develop immunity. If you do get sick, vaccines lower your risk of suffering from complications of the disease by increasing your body’s ability to fight the infection.

Vaccines also lower your chance of spreading disease to others around you. Some of your friends or loved ones may not be able to receive vaccines themselves due to their health condition. When healthy adults receive vaccines, it helps protect the whole community against the spread of serious diseases.

How effective are vaccines?

Vaccines are safe and highly effective for children and adults. Some are up to 99 percent effective at preventing disease.

By following the Centers for Disease Control and Prevention (CDC) recommended immunization schedule and getting vaccinated as suggested by your healthcare provider, you can protect your children, loved ones and yourself from serious vaccine-preventable diseases.

Today’s vaccines protect against more than 20 infectious diseases. Many vaccines are part of preventative care and regular wellness checks for children. Talk to your child’s doctor about the best strategy for vaccination.

Learn more about vaccines!

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Vaccines & School Attendance Requirements

For children to attend school, Louisiana state law requires that children receive specific vaccines according to their vaccine schedule. Learn more about these requirements and find additional vaccine resources below.