This post will kick off a series that will be providing information on each disease and vaccine that is currently on the CDC’s recommended national immunization schedule. I hope this information is able to help those attempting to decide on an alternative vaccine schedule (whether that is a delay, select or decline one). Please leave a comment if you have any questions.
The information below is gathered from sources included PubMed, the CDC, the Mayo Clinic, and package inserts published from the vaccine manufacturer. (See below for a full list)
The Disease
Hepatitis B infection is spread through contact with the blood or body fluids of someone who already has a hepatitis B infection.
Some common ways HBV is spread is through:
· Blood transfusions (which is not common in the US)
· Direct contact with blood in health care settings
· Sexual contact with an infected person
· Tattoos with unclean needles or instruments
· Shared needles during drug use
It is improtant to note that the hepatitis B virus can be passed to an infant during childbirth if the mother is infected. Due to this higher risk, pregnant women are tested for hepatitis B during their prenatal care. If you are not infected with hepatitis B while pregnant, you may want to consider delaying or declining this vaccine.
- If mother positive for HBsAg and HBeAg
- 70%-90% of infants infected
- 90% of infected infants become chronically infected
- If positive for HBsAg only
- 10% of infants infected
- 90% of infected infants become chronically infected
Symptoms
The majority of people infected with HBV experience no symptoms but if symptoms do appear they commonly consist of yellowing of the skin and eyes, fatigue, nausea, dark urine and abdominal pain.
If your body is healthy it will be able to fight off the hepatitis B infection, any symptoms will diminish over a period of weeks to months.
In some cases, a person’s body lacks the ability to completely get rid of the infection. This is what is called chronic hepatitis B.
Chronic hepatitis B occurs in less than 5% of adults. However, chronic infection occurs in almost all newborns that become infected (about 50% in children). Again, due to this higher risk, pregnant women are tested for hepatitis B during their prenatal care.
Interestingly, the majority of people who have chronic hepatitis B infection have no symptoms -although, damage to the liver may be occuring gradually over time. Another reason to be careful who you have sex with and to say no to drugs.
Treatment
Regular hepatitis B infection needs no treatment other then plenty of rest, fluids, and eating healthy foods. Hepatisis B is removed from the body after 2 - 3 weeks with the liver returning normal function within 4 - 6 months.
Antiviral medication (peginterferon) is utilized for patients with chronic hepatitis B. Althought there is no cure for hepatitis B, the majority of adults infected with HBV recover fully, even when they have severe symptoms.
Hepatitis B is fatal in approximately 1% of cases.
The Vaccine
Some background: Hepatitis B vaccines have been available in the US since 1981. Interestingly, the impact of vaccines on hepatitis has been less than ideal and this can be attributed to a few reasons.
For a decade after the introduction of the HBV vaccine in 1981, vaccination was targeted to only persons in high risk groups (heterosexuals with contact with infected persons or multiple partners, injection-drug users, and men who have sex with men). These high risk groups are difficult to include in a national vaccine program for many various reasons.
To alleviate this, in 1991 a new strategy to eliminate HBV was adopted. It included routine vaccination of all newborns and children – even though this group was the least likely to aquire infection it was most cost effective and simplest of solutions.
The ACIP in conjunction with the CDC recommends that all infants be vaccinated with three doses of hepatitis B vaccine beginning at 12 hours of age with the last dose given before 18 months of age.
Babies born from infected mothers will be given the hepatitis B immune globulin (HBIG) in addition to the vaccine at birth. Also worth noting, preterm infants or babies weighing less then 2,000 grams (4.5 lbs) should not receive the vaccine until 1 month or hospital discharge (except those born to infected moms).
There are two manufacturers in the US that produce the hepatitis B vaccine, Merck (Recombivax HB) and GlaxoSmithKline Pharmaceuticals (Engerix-B). These vaccines can be utilized in both adult and populations. These vaccines can also be used interchangeably, except for the two-dose schedule for adolescents (11 -15yrs - only Merck vaccine is approved for this schedule).
The hepatitis B vaccine is a recombinant vaccine. This means that a section of
This hepatitis recombinant vaccine is produced by inserting the surface protein of a hepatitis virus into common baker’s yeast. Yeast cells then produce HBsAg, which is collected and then purified. Recombinant vaccines are safer then most since infection of the virus cannot result from use of this vaccine since no infectious viral
Immunogenicity and Vaccine Efficacy
After three doses of the hepatitis B vaccine, it is estimated that approximately 90% of healthy adults and 95% of children develop an adequate antibody response. It is understood that an age-specific decline has been seen in immunity. According to the CDC, the studies that have been done on efficacy indicate that immunologic memory remains intact for 20 years among healthy vaccinated populations.
A note to those that may decide to delay this vaccine, the highest titers are achieved when the last two doses of the vaccine are spaced at least 4 months apart which makes this spacing preferable.
Quick info on some other options:
The Comvax vaccine is a hepatitis B vaccine in combination with Haemophilus influenzae type b (Hib) vaccine developed by Merck. Each dose of Comvax contains 225 mcg of aluminum with not more than 0.0004% (w/v) residual formaldehyde.
GlaxoSmithKline’s Pediarix vaccine was approved in 2002 and was the first 5-component (pentavalent) combination vaccine licensed in the US. Pediarix contains DtaP:(Infanrix), hepatitis B (Engerix-B), and inactivated polio vaccine. Pediarix contains the highest level of aluminum adjuvant at a level of 850 mcg. Each dose also contains ≤100 mcg of residual formaldehyde and ≤100 mcg of polysorbate 80 (Tween 80).
Pediarix cannot be used for the first dose at birth since the minimum age for dosage is 6 weeks. Pediarix is commonly utilized for the first three doses of the DTaP and IPV series, which are usually given at about 2, 4, and 6 months of age.
For those of you who might delay, Pediarix is approved for use through 6 years of age. So a child who is on a delay schedule can still receive Pediarix as long as it is to a child younger than 7 years of age.
A schedule for adolescents (11 or 12 years of age) is two doses separated by no less than 4 weeks, and a third dose 4 to 6 months after the second dose –the Engerix-B or Recombivax HB vaccine can be administered at this age.
Precautions to Vaccination with HBV
Children with moderate illness should not be vaccinated until their condition improves.
However, it is noted specifcally that a minor illness, such as an upper respiratory infection, is not a contraindication to vaccination. (If you ask me, I would wait until my child is healthy to vaccinate – but that’s just my two cents)
Studies of the safety of hepatitis B vaccine in pregnant women have not been performed and it is not known whether the vaccine will effect breastmilk.
Adverse Reactions
The most common adverse reaction following hepatitis B vaccine is pain at the site of injection. Fatigue, headache, and irritability have also been reported in up to 20% of children after vaccation. Fever can also occur and was seen in approximately 6% of children in the safety studies performed by the manufacturers.
Hepatitis B vaccine has been noted to cause or exacerbate multiple sclerosis. A 2004 retrospective study in a British population found a slight increase in risk of MS among hepatitis B vaccine recipients (study was published in Neurology-click here to review).
As of March 2012, there has been a total of over 66,000 hepatitis B vaccine-related adverse events reported to the federal Vaccine Adverse Events Reporting System (VAERS),
Search for Vaccine Reactions
Reporting a Vaccine Reaction
Reporting vaccine reactions to VAERS is the law. If your doctor will not report a reaction, you have the right to report a suspected vaccine reaction to VAERS. Here is the website to report a reaction: http://vaers.hhs.gov/esub/index
Whenever you make a health care decision for yourself or your child, especially one that involves a pharmaceutical product such as a vaccine, you should consider obtaining information from many different sources as well as consulting your health care professional.
Becoming an informed health care consumer is important and will empower you to ask doctors important questions and ultimately help you to take control of your health choices.
If your doctor is not supportive of your informed health choices, consider consulting another doctor who will work with you as a partner helping you make important health care decisions for yourself or your child(ren).
National Vaccine Information Center: Hepatitis B
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