How is vaccine used

These can already be found in the body or in food — usually in much larger quantities than the amount used in a vaccine. However, the most abundant ingredient in a vaccine is water. Some vaccines also contain aluminium — usually in the form of aluminium hydroxide.

Aluminium is found naturally in nearly all food and drinking water and is used in vaccines to strengthen and prolong the immune response they generate. Aluminium is also found in many other medicines, such as heartburn medication. It is an organic compound which is found in many living things and humans produce formaldehyde naturally as part of the metabolic process. While it is true that high levels of formaldehyde can be harmful to humans, the amount of formaldehyde present in any vaccine is fifty times smaller than that found in a pear.

Both can be found online. Immunisation is a proven tool for controlling and eliminating life-threatening infectious diseases and is estimated to avert between 2 and 3 million deaths each year - World Health Organization. How vaccines work How do vaccines work and why are they important? What is vaccination? How does vaccination work? Is it better for my child to get the disease naturally? How effective is vaccination? Have vaccines made a difference? If these diseases are so rare, why does my child need to be vaccinated?

How do I know vaccines are safe? What are vaccines made of? How do vaccines work? Is is better for my child to get the disease naturally? Scientists take many approaches to developing vaccines. These approaches are based on information about the infections caused by viruses or bacteria the vaccine will prevent, such as how germs infect cells and how the immune system responds to it.

Practical considerations, such as regions of the world where the vaccine would be used, are also important because the strain of a virus and environmental conditions, such as temperature and risk of exposure, may be different across the globe. The vaccine delivery options available may also differ geographically. Today there are five main types of vaccines that infants and young children commonly receive in the U.

There are four reasons that babies—and even teens or adults—who receive a vaccine for the first time may need more than one dose:. Some people believe that naturally acquired immunity—immunity from having the disease itself—is better than the immunity provided by vaccines. However, natural infections can cause severe complications and be deadly.

This is true even for diseases that many people consider mild, like chickenpox. It is impossible to predict who will get serious infections that may lead to hospitalization. Vaccines, like any medication, can cause side effects.

The most common side effects are mild. However, many vaccine-preventable disease symptoms can be serious, or even deadly. Although many of these diseases are rare in this country, they do circulate around the world and can be brought into the U. Even with advances in health care, the diseases that vaccines prevent can still be very serious — and vaccination is the best way to prevent them.

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Minus Related Pages. On This Page. Macrophages media icon are white blood cells that swallow up and digest germs, plus dead or dying cells. The macrophages leave behind parts of the invading germs called antigens. The body identifies antigens as dangerous and stimulates antibodies to attack them. B-lymphocytes are defensive white blood cells. They produce antibodies that attack the antigens left behind by the macrophages.

T-lymphocytes are another type of defensive white blood cell. They attack cells in the body that have already been infected. How Vaccines Work Vaccines help develop immunity by imitating an infection.

Types of Vaccines Scientists take many approaches to developing vaccines. These vaccines contain a version of the living virus or bacteria that has been weakened so that it does not cause serious disease in people with healthy immune systems.

The hepatitis B , shingles , human papillomavirus HPV , and one of the influenza vaccines are made this way. The vaccine is composed of a protein that resides on the surface of the virus. This strategy can be used when an immune response to one part of the virus or bacteria is responsible for protection against disease.

These vaccines can be given to people with weakened immunity and appear to induce long-lived immunity after two doses. Watch this video to see how genetic engineering is used to make effective vaccines. Some bacteria cause disease by making a harmful protein called a toxin. Several vaccines are made by taking toxins and inactivating them with a chemical the toxin, once inactivated, is called a toxoid.

By inactivating the toxin, it no longer causes disease. The diphtheria, tetanus and pertussis vaccines are made this way. Another strategy to make a bacterial vaccine is to use part of the sugar coating or polysaccharide of the bacteria.

Protection against infection by certain bacteria is based on immunity to this sugar coating and not the whole bacteria. However, because young children don't make a very good immune response to the sugar coating alone, the coating is linked to a harmless protein this is called a "conjugated polysaccharide" vaccine. The Haemophilus influenzae type B or Hib , pneumococcal , and some meningococcal vaccines are made this way.

Two meningococcal vaccines, which prevent one particular type of the bacterium type B not contained in the other meningococcal vaccines, are made using two or more proteins from the bacteria, not the bacterial polysaccharide.

Just like for inactivated viral vaccines, bacterial vaccines can be given to people with weakened immune systems, but often require several doses to induce adequate immunity. Using this strategy, the person who is vaccinated makes part of the virus. Similar to vaccination strategies that inject parts of a virus directly, this strategy can be used when an immune response to one part of the virus is capable of protecting against disease.

These vaccines can be given to people who are immune-compromised but require two doses to be protective. Currently, no DNA vaccines are commercially available.