WHY DOES MY CHILD NEED VACCINE?

INTRODUCTION

•   Vaccines are one of the most effective ways to prevent serious illness in children and adults. Vaccine programs in the United States have been quite successful in reducing the number of children affected by many highly contagious diseases, including measles, rubella, mumps, diphtheria, and polio.
• The following is a discussion of how immunizations work, common side effects, reasons to avoid a particular vaccine, and common concerns about vaccines. Separate articles discuss individual vaccines for children and adults.

HOW DO VACCINES WORK? 

•  The immune system functions to protect the body against illness and infection. When an organism (bacterium or virus) is foreign to the body, the immune system detects the organism and responds by creating proteins called antibodies. Antibodies fight the infection and help the person to recover.
• Antibodies also work to prevent a person from becoming ill in the future. If a person is exposed to the organism again, the immune system recognizes it and rapidly produces more of the antibodies required to destroy the organism. This response protects the individual from developing the disease, ideally for life. For example, a person who had chickenpox as a child is unlikely to develop it again, even if he or she is in close contact with a person who is infected.
• Vaccines work by stimulating the immune system to produce antibodies. However, unlike bacteria and viruses, vaccines do not cause the person to become ill in order to develop these antibodies. There are two main types of vaccines: active and passive.
• Active vaccines — Active vaccines use a weakened form of the harmful bacteria or virus to stimulate the immune system. Examples of active vaccines include vaccines that are used to prevent polio, measles, mumps, rubella (German measles), pertussis, etc.
• Some bacteria (eg, diphtheria, tetanus) cause illness because they produce harmful substances called toxins. Vaccines that help the immune system protect the body from toxins are called toxoids. Toxoids are made from weakened forms of the bacterial toxins.
• Passive vaccines — Passive vaccines provide temporary immunity using antibodies obtained from a large pool of donors; this type of preparation is known as immune serum globulin. Passive vaccines offer short-term protection to children or adults who have been exposed to a specific organism.
• One example of a passive vaccine is hepatitis B immune globulin (HBIG). HBIG is given to newborns whose mothers test positive for hepatitis B surface antigen (HBsAg). HBIG provides temporary protection to the newborn against infection with hepatitis B.

Vaccines protect children and adults — 

• Many parents are concerned about the risks of vaccines. However, vaccines have a long record of being a safe and effective way of preventing disease. In most cases, the benefits of vaccinating a child are far greater than any potential risks.
• Diseases such as diphtheria and measles were common at one time in the United States, but are no longer a significant threat because of vaccination programs. However, these illnesses are still common in developing countries throughout the world. Because it is easy to travel from one country to another, it is very possible for someone with a vaccine-preventable disease to enter the United States and transmit the disease to any child or adult who has not been vaccinated. Vaccination helps to reduce a child’s, family’s, and even an entire community’s chances of becoming ill by decreasing the number of people who could get sick and then transmit the infection to others. This process of protection is sometimes referred to as “herd immunity”.
• An example of a successful vaccination effort is the smallpox program. Before a vaccine was available, smallpox killed millions of people every year. Up until the early 1970s, smallpox disease was a worldwide threat to life. Use of the smallpox vaccine in large populations of people prior to the 1970s led to complete eradication of the disease. Because of this, the smallpox vaccination is no longer administered for routine protection.

How are vaccines given? 

•  In children, most immunizations are given in the form of a shot. Vaccines are also given in other ways, such as in a liquid taken by mouth (eg, rotavirus) or as a nasal spray (eg, one form of the influenza vaccine).
• Paying for vaccines — Vaccines are available for every child in the United States, even for those who do not have health insurance. If a child does not have health insurance and the parents are unable to pay for vaccines, a program called Vaccines for Children is available. This program helps to cover the costs of vaccines given at private doctor’s offices, clinics, hospitals, community health clinics, and in some schools.

VACCINE SIDE EFFECTS 

•  Most vaccines and toxoids are safe and cause few if any serious side effects. Very rarely, serious side effects do occur. Children who develop unusual reactions such as rashes involving much of the body surface, difficulty breathing, excessively high fevers, seizures or loss of consciousness within a short time after receiving a vaccine should be evaluated by a healthcare provider..

Mild side effects — Vaccines and toxoids can occasionally cause mild side effects, including:

●A low-grade fever

●A red and tender area at the site of an injection

Moderate side effects — Occasionally, children can develop a combination of fever, skin rash, swollen lymph nodes, and/or joint pain after vaccination. These reactions, called serum sickness-like reactions, can be uncomfortable, although they are rarely dangerous and resolve without treatment in days to weeks.

Severe side effects — Severe side effects of vaccines are rare, but may include a severe neurologic reaction (eg, seizures) or severe allergic reactions (eg, anaphylaxis). Allergic reactions usually occur within minutes to hours of receiving the vaccine. If this occurs in the doctor’s or nurse’s office, emergency care can be given immediately. If a severe reaction occurs away from the doctor’s or nurse’s office, the parent/guardian should call emergency medical services, available in most areas of the United States by dialing 911.

Reasons to avoid vaccination — A particular vaccine may not be recommended for children with a serious allergic reaction to the following:

●Eggs or egg protein, since some vaccines are prepared with embryonic chicken eggs or cultures (eg, influenza vaccines, yellow fever vaccines). A mild allergic reaction to eggs does not mean that the vaccine should be avoided.

●The antibiotic medications neomycin or streptomycin (some vaccines contains trace amounts of neomycin)

●Gelatin

●A specific vaccine administered in the past

In some cases, parents may not know their child is allergic to one of these components until the vaccine is given and the child develops a reaction.

In addition, live virus vaccines (eg, the measles, mumps, and rubella vaccine) are generally not recommended for children with a weakened immune system since there is an increased risk of infection as a result of the vaccine. However, there may be exceptions to this recommendation.

Administration of the measles-mumps-rubella and varicella vaccines should be delayed in children who have recently received a blood transfusion or blood products (eg, immunoglobulin preparations) since these products can make the vaccine less effective.

Conditions that do not affect vaccination — The following conditions do not require delaying or avoiding vaccines:

●Current or recent mild illness

●Current or recent antibiotic therapy

●Previous mild to moderate tenderness, redness, or swelling at the site of injection or fever less than 104.9ºF (40.5ºC) after a previous vaccination

●A personal history of allergies, except those listed above

●A family history of adverse reactions to vaccines

Are vaccines safe for my child? — There have been concerns about the safety of vaccines for children.

One concern was related to a particular preservative (thimerosal) that was previously used in a number of different vaccines. The concern centered around the possibility of any relationship between the administration of certain vaccines and autism. Thimerosal is a derivative of mercury that was previously used as a preservative in most vaccines. As the number of vaccinations given to infants increased, there was concern that this preservative could lead to potentially unsafe levels of mercury levels in some infants. As a result, several expert groups recommended in 1999 that all standard childhood vaccines be produced without thimerosal. The recommendation was a precautionary change and was not based upon known harm from thimerosal. Thimerosal-free forms of all of the childhood vaccines are available in the United States. A large number of studies throughout the world have failed to show any cause and effect relationship between autism and those vaccines that contained thimerosal.

A second concern was in regards to a possible relationship between certain vaccines and the development of autism. Despite this concern, there is no scientific evidence that receiving these vaccines causes or increases the risk of developing autism.

Studies that had previously raised the possibility of a relationship had significant weaknesses in their design. A number of the studies were based on a small number of children and relied upon the memory of parents or pediatricians to recall when behavioral signs/symptoms related to autism began. Most studies did not include a control group to compare children who were vaccinated with those who were not vaccinated to determine if there was a cause and effect relationship. At least some cases of autism are most likely attributable to gene abnormalities.