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Health of Infants and Children
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Childhood Vaccines

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Hepatitis A Vaccine is Safe and Effective for Children

Hepatits A is a virus transmitted by contaminated food and is a common cause of inflammation of the liver (hepatitis). This illness may be associated with fever, yellowing of the skin and eyes (jaundice), loss of appetite, nausea, vomiting, and tiredness. In many parts of the world, hepatitis A is so common that almost every adult has been infected at some point in his or her life. A vaccine to protect against hepatitis A infection was licensed in the United States by the Food and Drug Administration in 1995 for individuals 2–12 years of age.

A recent study published in the Journal of the American Medical Association showed that the hepatitis A vaccine was highly effective in preventing hepatitis A outbreaks among a large group of children who received it. The study also found the vaccine to be quite safe. Out of the nearly 30,000 children who received the vaccine, no serious side effects were reported. Mild adverse reactions were reported in a small percentage of cases, including injection site reactions, fever, and rash.

Should your child be immunized? In the United States, there actually are certain areas of the country with higher than average rates of hepatitis A. Speak with your child's pediatrician because the hepatitis A vaccine is currently recommended for:

  • Children living in areas with consistently higher rates of hepatitis A. This includes 11 states where the prevalence of hepatitis A is greater than twice the national average: Alaska, Arizona, California, Idaho, Nevada, New Mexico, Oklahoma, Oregon, South Dakota, Utah, and Washington. (Routine vaccination can also be considered in six states where the prevalence of the disease is less than double but greater than the national average: Arkansas, Colorado, Texas, Missouri, Montana, and Wyoming.)
  • Children traveling to countries where the disease is highly prevalent. This includes all countries other than Canada, Japan, Australia, New Zealand, Scandinavia, and those in Western Europe.
  • Children with chronic liver disease or blood-clotting disorders.

April 2002 Update

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Immunizations for 2002

Vaccinations against childhood illnesses are arguably one of the most significant medical achievements of the twentieth century. One hundred years ago, approximately half of all children born in the United States died before the age of 5, many of them from diseases that today can be prevented by vaccines. With proper immunization, the number of cases of these diseases has been reduced dramatically.

Although no new vaccines have been added to the 2002 recommended childhood immunization schedule, this year's schedule highlights vaccines for pre-adolescents and "catch-up" vaccines for children who have fallen behind the currently recommended schedule.

In addition, due to unusual national shortages of the pneumococcal and diphtheria/tetanus/pertussis vaccines, the 2002 immunization schedule also includes a link to information from the Centers for Disease Control (CDC), which explains the necessary modifications to the recommended schedule for these vaccines. These vaccine shortages will hopefully only be temporary.

Please discuss your child's immunization history with the doctor to insure that his or her immunizations are up to date in accordance with the current 2002 Recommended Childhood Immunization Schedule, approved annually by the CDC, the American Academy of Pediatrics, and the American Academy of Family Physicians. For additional reliable and up-to-date information about vaccines and their importance, visit the National Immunization Program website at or the American Academy of Pediatrics website at
April 2002 Update

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Vaccine safety: no link between thimerosal and neurodevelopmental disorders

Parents should feel confident and safe when having their children immunized. No evidence exists that proves a link between thimerosal-containing vaccines and neurodevelopemental disorders, such as autism, attention deficit-hyperactivity disorder, or speech and language delay. The Institute of Medicine recently reported these findings, consistent with the recommendations of the American Academy of Pediatrics.

Thimerosal, a mercury-containing preservative, was used for many years in vaccines to prevent contamination. Taking in a high dose of mercury is toxic to the human nervous system. But because of the increasing number of vaccines routinely recommended for infants, concern was raised in 1999 by the Food and Drug Administration that the total amount of mercury contained in the vaccinations could be exceeding the recommended mercury levels for infants.

Although there's no data to suggest thimerosal caused any harm, the American Academy of Pediatrics and the U.S. Public Health Service have requested manufacturers remove thimerosal from vaccines. As a result, most, if not all, childhood vaccines are now thimerosal-free.

The Institute of Medicine's recommendations emphasized the importance and continued safety of childhood vaccination. Parents should definitely be reassured that all routine childhood immunizations are in their children's best interests, as they clearly have been shown to prevent potentially life-threatening diseases.
November 2001 Update

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Breast-Feeding May Protect Against Childhood Asthma

Another vote in favor of breast-feeding! Researchers in Western Australia found that babies who are fed breast milk exclusively for their first four months are less likely to develop asthma by age 6. Asthma is the leading cause of hospital admissions for Australian youth. In the United States, it affects about 17 million Americans and about a quarter of all children under 18.

To determine whether there was a connection between asthma and breast-feeding, the researchers compared questionnaires completed by parents when their children were a year old with questionnaires completed when the children were 6. The surveys asked about breathing problems, feeding (length and exclusivity of breast-feeding), smoking in the home, and daycare (to evaluate exposure to respiratory infections).

The age at which a child was fed soy or cow's milk was more positively associated with asthma and wheezing. Introduction of milk other than breast milk before four months was a significant risk factor for the development of asthma by age 6. According to the Food and Drug Administration, babies who are breast-fed have lower rates of hospital admissions, ear infections, diarrhea, rashes, allergies, and other medical problems than bottle-fed babies. Because human milk contains cells that kill bacteria, fungi, and viruses, breast-fed babies are protected from a number of illnesses. To learn more about breast-feeding, see page 951 of the Family Health Guide. If you are unable to breast-feed, see page 505 for more information about other ways to prevent childhood asthma. Controllable risk factors include the presence of house dust and tobacco smoke.

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New Pneumococcal Vaccine for Children Less Than Two Years Old

A new vaccine called Prevnar is the first vaccine to protect children less than two years old against the bacteria Streptococcus pneumoniae, which is the leading cause of pneumonia, bacterial meningitis, bacteremia, sinusitis, and acute otitis media, or middle-ear infections, in young children. In addition to protecting children from pneumococcal infection, vaccination with Prevnar also decreases transmission of pneumococci from one child to another, an effect known as "herd immunity." Furthermore, since middle-ear infections are the leading reason that children need to take antibiotics, vaccination with Prevnar could reduce the need for antibiotics in this age group. This, in turn, should slow or reverse the trend of antimicrobial resistance. A different pneumococcal vaccine, known generically as PPV23, has been available to adults for years, but it has not been effective in children less than two years old.

The Centers for Disease Control and Prevention's (CDC's) Advisory Committee on Immunization Practices (ACIP) recommends that all children less than two years old should be vaccinated with Prevnar. Children aged two to five years old should receive a two-shot series of Prevnar followed by one dose of PPV23 if they are high-risk, a category that includes children with HIV, immunocompromising conditions, chronic illness, or sickle cell disease. Prevnar may also be considered for children between two to five years with priority given to those who are between the ages of 24 and 35 months, of African-American, American Indian, or Alaska Native descent, or who attend group day care centers.

Since Prevnar has not been studied sufficiently in children older than five years who are at high risk for serious pneumococcal disease, ACIP continues to recommend that children five and older receive PPV23.

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