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Immunization

Vaccine administered, usually to a baby or child, to prevent infection with a specific serious illness.

People are given immunizations to protect them from serious illnesses. The vaccines used in immunization are actually weakened doses of the organism that causes the disease. These organisms trigger the person's own immune system to produce antibodies against the disease. In this way, if the person ever comes into contact with the disease, his body will be prepared to fight it. Immunization schedules vary widely from country to country. In the Unites States, the American Academy of Pediatrics (AAP) issues recommendations for immunization of babies and young children. Eight major childhood diseases are covered by this schedule: polio, measles, mumps, German measles (rubella), whooping cough (pertussis), diphtheria, tetanus (lockjaw), and meningitis and other haemophilus infections. Although in most developed countries these diseases are not very common, any one of them could cause disability or death. Immunizations should be taken seriously. Children traveling to other countries should be immunized according to the recommendations of public health officials familiar with the country the child will be visiting. All families should maintain records, signed by a doctor, regarding their schedule of immunizations. The Childhood Vaccine Injury Act was passed in 1986 to provide compensation to families for injury or death related to complications from immunizations.

DTP Vaccine

The DTP vaccine, immunizing against diphtheria (D), tetanus or lockjaw (T), and pertussis or whooping cough (P), is given in five injections, usually in the buttocks, upper thigh, or upper arm. The DTP vaccine is recommended for almost all young children. All 50 U.S. states require that children be immunized against diphtheria before entering school; nearly all require immunization against tetanus, and roughly 35 require immunization against pertussis. The first three doses are given at two, four, and six months of age. The next two are given at around 18 months and between four and six years of age, usually before the child enters school. If a child has ever experienced a seizure, the pediatrician may administer only the diphtheria and tetanus portions of the vaccine.

Side effects. Some infants experience mild side effects, such as a low-grade fever (less than 102°F or 38.9°C), irritability, listlessness, and redness and sensitivity in the area where the injection was given. These symptoms may be treated with acetaminophen, but should not be treated with aspirin. About one child in every 100-1,000 receiving the DTP vaccine may experience more serious side effects, such as constant crying for more than three hours, high fever (105°F or 40.6°C), or high-pitched, scream-like crying. Even more rare (about one for every 1,750 cases) are seizure (jerking, staring episode, usually associated with high fever) or collapse (limp, pale, and unresponsive). A pediatrician should be notified immediately if a baby or child exhibits any symptoms beyond the mild side effects after receiving the DTP vaccine. Although there has been some controversy about the DTP vaccine because of the side effects, the American Academy of Pediatrics strongly recommends this immunization for most children on the grounds that the benefits far outweigh the slight risk.

Related vaccines include DTaP (diphtheria, tetanus acellular, pertussis) vaccine, which is less likely to cause even the mild side effects of DTP and may be used for the 4th or 5th doses of DTP immunization; and DT (diphtheria tetanus) vaccine, which does not provide immunization against pertussis, and is not recommended for most healthy children.

MMR vaccine

The MMR vaccine, immunizing against mumps, measles (rubeola), and German measles (rubella), was licensed by the Food and Drug Administration in the United States in 1971. It is normally administered at about 15 months of age.

Side effects. Most children do not experience side effects from the MMR vaccine. Occasionally, beginning seven to ten days after the immunization, the child may have one or more of these reactions: mild skin rash, slight swelling of the lymph nodes in the neck or groin, low-grade fever (less than 102°F or 38.0°C), sleepiness, or slight pain in the joints. One special note about side effects, however, is that eggs are used in the manufacture of the MMR vaccine, and the pediatrician should be aware of any allergic reaction to eggs the child may have exhibited prior to the administration of the vaccine.

Polio vaccine

Polio (poliomyelitis) is a disease caused by a virus. In mild cases, the person will experience fever, sore throat, nausea, and pain and stiffness in the spine and legs. In more severe cases, known as paralytic polio, the disease can cause paralysis of some muscles of the body and can cause death in its most serious cases. Fortunately, the incidence of polio has become rare since vaccines became widely available in the 1950s. The most common vaccine in use in the late 1990s was developed by Albert Bruce Sabin in the late 1950s. It is the oral, live-virus vaccine, referred to as Oral Polio Vaccine (OPS) or Sabin oral vaccine. OPV is given in four doses, at two and four months of age, between six and eighteen months, and between four and six years of age. (A fifth dose may be prescribed if the child lives in or is traveling to a country where polio is more prevalent than it is in the United States.) The advantages of OPV are that it provides a strong, permanent immunity to polio, and can be painlessly administered orally.

Side effects. The oral, live-virus vaccine is, as its name implies, a live virus. Therefore, the polio virus will be present in the infant's or child's stools for several days after the vaccine is given. A nonimmunized individual coming into contact with the stool could be infected. If a parent of caregiver is not immunized against polio, the pediatrician should be informed before the vaccine is given. Other individuals who could be susceptible to the live virus include anyone with a compromised immune system such as children with leukemia, those being treated with long-term steroids, receiving treatment for any kind of cancer, or those infected with HIV. In these cases, inactivated polio virus (IPV) is the safe choice for immunization against polio.

The OPV was not the first vaccine to be developed against polio. An alternative, the inactivated polio vaccine or IPV, was developed by Jonas Salk and was first available to the public in 1954. The IPV is given by injection in the leg or arm, rather than administered orally, and provides less vigorous immunity than the OPV.

Side effects: Individuals who are allergic to the drugs neomycin or streptomycin should not receive IPV. Pregnant women can safely receive either OPV or IPV.

Haemophilus influenzae type B conjugate vaccine

The Haemophilus influenzae type B (HiB) conjugate vaccine provides immunity to bacterial infections cause by the Haemophilus influenzae B bacteria. Examples of these infections are meningitis and epiglottitis.

Hepatitis B virus vaccine

The hepatitis B vaccine provides immunity against the hepatitis B virus (HBV) which can cause serious illness, especially chronic liver disease. Immunization for infants and young children is important because early infection with HBV greatly increases the likelihood that the virus will cause liver failure in adulthood. All mothers are tested for HBV at the time of giving birth. Babies whose mothers test positive for HBV must receive the first dose of vaccine at or immediately after birth. In addition, those babies receive a dose of hepatitis B immune globulin (HBIG), and receive the other two recommended doses of vaccine on an accelerated schedule.

Side effects. No serious adverse reactions are linked to the hepatitis B vaccine. The mild effects that may occur include fussiness, soreness, swelling, or redness at the site of the injection. These symptoms, when they occur,

Age	Recommended immunizations
Notes:
(1) Three HiB {Haemophilus influenzae type B) conjugate vaccines have been licensed in the United States for use with infants. There are slight variations in the recommended sequence of immunizations.
(2) In the United States, no routine immunization for tuberculoses is recommended. All children are tested for tuberculoses with a skin-prick test on the forearm, often through the schools. Children with positive skin test results are investigated further to determine whether treatment is required.
(3) The second MMR vaccine is recommended at either 4-6 years or 11-12 years; however, it may be administered anytime, provided one month has elapsed since the administration of the first dose.
(4) Children who have not been vaccinated previously and who lack a reliable history of chicken pox should be vaccinated by age 13. VZV can be administered anytime after 12 months of age; children under 13 years receive a single dose; persons 13 and older should receive two doses administered 4-8 weeks apart.
(5) Lifelong immunization to tetanus and diphtheria requires inoculations—so-called "booster shots"—of vaccine theoretically every 10 years. In practice, only the tetanus booster is routinely given because the risk of contracting tetanus is significant enough to warrant it. Diphtheria has been nearly eradicated in the United States, so boosters are only prescribed in communities where cases of diphtheria have been reported.
Adapted from Recommended Childhood Immunization Schedule, United States, January-June 1997, approved by the Advisory Committee on Immunization Practices (ACIPT), American Academy of Pediatrics (AAP), and the American Academy of Family Physicians (AAFP).
4 months	Diphtheria, tetanus, and pertussis (DTP) Polio (OPV or IPV) Hepatitis B (HBV) Haemophilus influenzae type B (HiB) (1 )
6 months	Diphtheria, tetanus, and pertussis (DTP) Hepatitis B (HBV) Haemophilus influenzae type B (HiB)
12-15 months	Haemophilus influenzae type B (HiB) Tuberculosis test (2)
12-18 months	Diphtheria, tetanus, and pertussis (DTP) Polio (OPV or IPV) Varicella zoster (chicken pox) vaccine (VZV)
15 months	Measles, mumps, and rubella (MMR) vaccine Hepatitis B (HBV)
4-6 years	Diphtheria, tetanus, and pertussis (DTP) Polio (OPV or IPV) Measles, mumps, and rubella (MMR) vaccine (3)
12-14 years	Varicella zoster (chicken pox) vaccine (VZV) (4)
14-16 years	Tetanus-diphtheria booster (5)

begin within 24 hours of receiving the vaccine and are gone with 48-72 hours.

Varicella zoster (chicken pox) vaccine (VZV)

The varicella zoster vaccine to protect children against the common childhood disease known as chicken pox was approved for use in the United States in the early 1990s. It was tested in Japan in the 1970s, and in the United States during the 1980s in over 9,400 healthy children and 1,600 adults. The VZV is 70-90% effective in preventing chicken pox. If a vaccinated child does contract chicken pox, his or her case will be generally mild, with fewer skin lesions (15-30), a lower fever, and quicker recovery. Vaccinated children who get chicken pox are contagious, and can infect others with the disease. As of the mid-1990s, a booster for the VZV is not recommended, but studies were underway to determine how long immunity from the vaccine lasts.

Side effects. Most children experience only mild side effects from this vaccine. These include redness, tenderness, swelling, or a mild rash of several small pimples where the injection was given; tiredness, fussiness, mild fever, and nausea. The rash or pimples may also appear elsewhere on the body, and can occur up to one month after the injection was given. The VZV can be given at the same time as other recommended childhood vaccines, including DTP, polio, hepatitis B, and Haemophilus influenzae type B. It can also be given at the same time as the MMR vaccine. If the VZV and MMR are not given together, however, there should be at least a one-month interval between the two vaccines.

Other vaccines may be recommended for specific situations, and the pediatrician's advice should be sought and followed. Travel to tropical countries may require immunization for one or more diseases, such as cholera, typhoid fever, and yellow fever. Side effects from these vaccines are more severe than for the routine immunizations of childhood, and must be weighed against the necessity of the travel. Certain children with special needs may also be given the vaccines against influenza, pneumoccus, and rabies.

For Further Study

Books

Bellet, Paul S. The Diagnostic Approach to Common Symptoms and Signs in Infants, Children, and Adolescents. New York: Lea and Febiger, 1989.

Garwood, John, and Amanda Bennett. Your Child's Symptoms. New York: Berkeley Books, 1995.

Organizations

American Academy of Pediatrics, Division of Publications
Address: 141 Northwest Point Blvd., P. O. Box 927
Elk Grove Village, IL 60009-0927
(Publishes brochures on most immunizations and childhood diseases, and a 24-page booklet for parents that includes forms for tracking immunizations and other health-related information.)

National Institute of Allergy and Infectious Diseases (NIAID)
Address: 9000 Rockville Pike
NIH Building 31, Room 7A50
Bethesda, MD 20892-2520
(Arm of the National Institutes of Health that deals with allergies and diseases.)

National Vaccine Information Center
Address: 128 Branch Road
Vienna, VA 22180
(Organization also known as Dissatisfied Parents Together [DPT]. Comprised of parents whose children have had adverse reactions to vaccines, particularly to the DTP vaccine. Publishes DPT News, Parent Information Packet, and The Compensation System and How It Works.)