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Hepatitis A And B Vaccines Protect Kids Now And Later

Date:
August 24, 1999
Source:
Cedars-Sinai Medical Center
Summary:
Hepatitis B is believed to be the most common cause of chronic hepatitis, cirrhosis and liver cancer. Some school districts are requiring vaccination before seventh-graders, kindergarteners and pre-schoolers can enroll.
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LOS ANGELES -- Beginning July 1, students headed into the seventh grade in Los Angeles County had to first have to stop by the doctor’s office to be vaccinated against hepatitis type B. The vaccination was already required for entry into kindergarten and day-care centers but the new law ensures that all children are immunized before reaching adulthood.

Deborah Lehman, M.D., associate director of pediatric infectious diseases at Cedars-Sinai Medical Center, says hepatitis B is rarely seen in children but the vaccination program is the best way to protect kids from the disease as they grow older. Hepatitis B is usually transmitted by sexual contact with someone who is infected or by contact with blood that might occur in IV drug abuse and the sharing of infected needles. In the past, receiving a blood transfusion significantly increased risk, but the blood supply has been screened for hepatitis B since 1975.

“The young infants we’re immunizing are not IV drug abusers, they’re not sexually active, and household contact is a very infrequent cause of transmission,” says Dr. Lehman. “But in about one-fourth of cases of hepatitis B, the cause is unknown. And the disease is probably the most common cause of chronic hepatitis, cirrhosis and liver cancer. Furthermore, the earlier a person is infected in life, the more likely they are to develop these life-threatening illnesses as an adult. Therefore, immunizing children today against hepatitis B is a preventive measure. In the long term, we’re preventing liver cancer.”

Although sexual activity and drug involvement may not pose immediate threats to children, many adolescents are involved in two seemingly innocent activities – body piercing and tattooing – that increase their risk for acquiring hepatitis B and another potentially deadly virus called hepatitis C.

Few if any sterilization regulations exist within these industries, and the viruses can be spread though a very small amount of infected blood. Therefore, even getting ears pierced in a store that does not properly clean or dispose of contaminated equipment can increase the risk of transmission.

The term “hepatitis” refers to any inflammation of the liver, which can result from such diverse events as viral infections, exposure to toxic chemicals or long-term alcohol abuse. Hepatitis B is caused by a specific virus. Type A, caused by a different virus, does not lead to the degenerative liver disease associated with hepatitis B, but it can cause sudden, violent illness that quickly spreads through an entire family or community. Strangely, while children often spread the disease, they tend to remain symptom-free while the adults they contact become ill.

“Hepatitis A causes serious flu-like symptoms, including severe stomachache, diarrhea, vomiting and fever. The liver becomes inflamed and infected and loses its ability to process bilirubin, which causes the yellowing of eyes and skin called jaundice,” says Dr. Lehman. “Infected people often have to be hospitalized, for a couple of reasons. First, because they are unable to tolerate anything by mouth, patients become dehydrated. Also, because an infected liver may not be able to properly manufacture clotting factors, there is a tendency to bleed, which can be dangerous.”

Hepatitis A infection can be sufficiently severe to cause acute liver failure, requiring transplantation for survival. On the other hand, patients who become infected but recover will be immune to future infection.

According to Dr. Lehman, all adults and children in Los Angeles County may be required to receive hepatitis A vaccinations in the near future because the area is considered to have a high rate of infection – more than 20 cases per 100,000 population. In the meantime, however, vaccination is urged for people in high-risk categories, such as those who travel internationally; American Indians, native Alaskans and others in highly affected communities; homosexual and bisexual men; and patients such as those with hemophilia who receive clotting factor.

“Many people are understandably hesitant when they hear about new vaccines. It seems like there’s a new one every couple of months,” says Dr. Lehman. “But in the big picture, two shots for hepatitis A over six months is a minor inconvenience compared to the possibility of hospitalization, the possibility of an entire family being infected, and the possibility of death. These vaccines are very safe and very effective, and there will probably be a combination hepatitis A/hepatitis B vaccine available in the future, reducing the number of injections that will be required.”

The virus for hepatitis A is transmitted through fecal/oral contamination. In even less glamorous terms, a microscopic amount of the secretion from an infected person must somehow get into the another person’s mouth for the virus to be passed. This is why food preparers must wash their hands after using the restroom, and why an outbreak of hepatitis A can occur very quickly in a day-care center.

“Truthfully, little kids aren’t very careful about washing their hands after they use the bathroom,” says Dr. Lehman. “And, of course, kids put things in their mouths all the time. This can be a big problem in a day-care center where kids are running around in leaky diapers and putting their hands in their mouths. With hepatitis A being quite contagious, it can go through a community at a fairly rapid rate.”

In fact, the kids may pass the disease around, remaining asymptomatic, then take the virus home to their relatives who become violently ill. For this reason, vaccinating the children may help protect not only their health but that of their older, less robust family members, as well.

To reduce the risk of infection of either hepatitis A or hepatitis B, Dr. Lehman urges parents to have their children immunized against both viruses. Also, because there is a chance that organisms, including the virus that causes hepatitis B, can be transferred from one person to another through small amounts of contaminated blood, children should be cautioned against sharing toothbrushes and other personal items.

“There are playground accidents and other circumstances in which kids are exposed to other people’s blood. I think it’s a good idea for parents to take the initiative to teach kids about taking precautions and using good hygiene,” says Dr. Lehman. “It isn’t necessary to make them excessively anxious but it is important for kids to learn such things as washing their hands after using the bathroom.”


Story Source:

The above post is reprinted from materials provided by Cedars-Sinai Medical Center. Note: Materials may be edited for content and length.


Cite This Page:

Cedars-Sinai Medical Center. "Hepatitis A And B Vaccines Protect Kids Now And Later." ScienceDaily. ScienceDaily, 24 August 1999. <www.sciencedaily.com/releases/1999/08/990823205652.htm>.
Cedars-Sinai Medical Center. (1999, August 24). Hepatitis A And B Vaccines Protect Kids Now And Later. ScienceDaily. Retrieved July 28, 2015 from www.sciencedaily.com/releases/1999/08/990823205652.htm
Cedars-Sinai Medical Center. "Hepatitis A And B Vaccines Protect Kids Now And Later." ScienceDaily. www.sciencedaily.com/releases/1999/08/990823205652.htm (accessed July 28, 2015).

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