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an individual received the hepatitis B immunizations in 1984,
was that vaccine different than is given now? And does the individual
need to be revaccinated?
A person vaccinated in 1984 would have gotten the plasma-derived
hepatitis B vaccine (the recombinant vaccine was licensed in
1986). The plasma-derived vaccine was effective, and anyone
who got a complete series does not need to be revaccinated using
the newer vaccine. (6/26/03)
I am exposed to hepatitis B, and have not received the series
of immunizations, would I receive any protection from that
exposure by starting the series at that time? In other words,
is it to late to start the series after the exposure?
for hepatitis B post-exposure prophylaxis are included in the
ACIP recommendations for healthcare workers, ftp://ftp.cdc.gov/pub/Publications/mmwr/rr/rr4618.pdf,
(see page 23), and in hepatitis B chapter of the Pink Book,
The vaccine is part of the recommended prevention treatment
following an exposure along with HBIG, which provides temporary
antibody protection until the person’s immune system can
develop antibodies in response to the vaccine series. If you
were not infected by the exposure, the vaccine will offer protection
from possible future exposures. If you were infected, the vaccine
will not harm you, but would be of no benefit. (6/26/03)
a dose of 1 ml of 10 mcg Engerix B (2 vials of the Pediatric
dose) be the same as 1 ml of 20 mcg (1 vial of the Adult dose)?
The pediatric formulation of Engerix-B is not licensed by FDA
for use in adults. Adults 20 years of age and older should receive
1 mL (20 mcg) of the adult formulation of Engerix-B. With Recombivax
HB, two pediatric doses can be used in place of an
adult dose, because Recombivax is licensed for that usage. (6/26/03)
you clarify the age groups for the various hepatitis B vaccine
(Merck) is approved by FDA such that either vaccine (pediatric
or adult) can be used for people of any age. For the routine
3-dose schedule, persons <20 should receive 0.5 ml per dose,
and those 20 and older should receive 1.0 ml per dose. The 2-dose
"adolescent" schedule for children 11-15 years of
age is two 1.0 ml dose separated by at least 4 weeks.
Engerix-B (GSK) is NOT approved for this use. Pediatric vaccine
can be used through age 19. The pediatric formulation is not
approved for use in persons 20 years and older.
Twinrix is licensed for use in persons 18 years of age and older.
do I do if a worker wants the hepatitis B series but can’t
remember if they have already had the vaccine, or they can’t
remember how many doses they got?
safest option when there is no documentation is to vaccinate.
You could test to ascertain if the person has a protective level
of antibodies (anti-HBs = >10 mIU/Ml). (6/26/03)
it true that the hepatitis B virus can live for months on a
surface and infect someone if they have a cut or break in the
hepatitis B virus is a hardy virus and probably lives on surface
for several weeks, but not months. Infection from contact with
a surface is not likely, because the material dries and doesn’t
penetrate through the skin. It is theoretically possible, but
in reality probably very rare. (6/26/03)
an infant receives the second Hepatitis B dose 24 days after
the first dose and the third dose is administered 3 or 4 days
before the child is 6 months of age, would this be considered
a valid series?
Yes, but just barely. In this case the child has had the interval
between the first and second doses reduced by the 4-day grace
period. The minimum age for the third dose of Hepatitis B vaccine,
which is 6 months, has also been reduced by the 4-day grace
This sort of immunization practice is not ideal. The grace period
is a last resort, not something that one uses for scheduling.
By ACIP’s definition, these doses would both be valid
because they fall within the 4 days recommended by ACIP. But
that does not mean a state will accept them as valid. Some states
do not accept the 4-day grace period for any dose of any vaccine
because of complexities of day care and school laws. Any time
you are giving vaccines that close to the bare minimum, you
really need to rethink how to give vaccines according to the
actual recommended schedule. ACIP
General Recommendations (see page 3). (2/13/03)
you clarify the hepatitis B vaccine minimum intervals?
hepatitis B minimum intervals are as follows:
may use weeks (1 month = 4 weeks) to calculate intervals up
to 4 months. Beyond 4 months, you should use calendar months.
work at a residential facility for children. Many of the kids
who come into my care are behind on their vaccines, especially
the Hepatitis B series. Many of these kids are sexually active.
Can I routinely follow the catch-up schedule for them? Sometimes
they are here for less than six months.
Yes, you can follow the schedule using the minimum intervals.
You must have at least 4 weeks (28 days) between doses one and
two, at least 2 months (8 weeks) between doses two and three,
and at least 4 months (16 weeks) between doses one and three.
That’s as close together as you can give the doses. ACIP
General Recommendations (see page 3) (2/13/03)
I received the first two shots in the hepatitis B series, but
did not receive the third, and it is now 10 years later, should
I go ahead now and get the last one?
of when you started the hepatitis B series, you should just
pick up where you left off and complete the series. It is not
necessary to add doses or restart the series if the interval
between doses is longer than recommended. (6/26/03)
inactivated fractional vaccines, specifically Td, require booster
doses every ten years, why are routine hepatitis B booster doses
Available data show that vaccine-induced hepatitis B antibody
levels do decline with time. Nevertheless, immune memory remains
intact for at least 15 years following immunization, and both
adults and children with declining antibody levels are still
protected against significant hepatitis B virus (HBV) infection
(e.g., clinical disease, HBsAg antigenemia, or significant elevation
of liver enzymes). Exposure to HBV results in an anamnestic
anti-HBs response that prevents clinically significant HBV infection.
Chronic HBV infection has only rarely been documented among
For adults and children with normal immune status, booster doses
of vaccine are not recommended nor is routine serologic testing
to assess immune status. The need for booster doses after longer
intervals will continue to be assessed as additional information
becomes available. Pink
Book Chapter: Hepatitis B (2/13/03)
is your recommendation if a person who is tested for Hep B antibodies
following completion of vaccination is found to be nonreactive
to the Hep B antibodies? Also,
what if a person has a blood exposure and is found to be nonreactive
to Hep B antibodies even though they have completed the vaccination
for hep B and may have had a earlier reactive antibody result
to Hep B antibodies. And
what if someone has not had a previous reactive antibody test
done after completion of vaccination?
The key to the first question is how long after the hepatitis
B series the testing is done. As the question is worded, it
appears to be about testing done immediately after vaccination
(1-2 months). In this case, the answer is that this person should
get another 3-dose vaccine series and be tested again after
the third dose. (NOTE: If the person has already had two complete
hepatitis B vaccine series, additional doses are not recommended.
The person should be considered a non-responder.)
person whose immune status is in doubt, who has a percutaneous
or permucosal exposure to blood known to be infected with hepatitis
B virus, should get one dose of HBIG and a booster dose of hepatitis
B vaccine. (For more details see CDC guidelines at http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5011a1.htm,
post-vaccination antibody testing is not recommended, except
for certain groups (e.g., people at high risk of blood exposures)
and only if it is done within 2 months of vaccination. Otherwise
the result could be negative, even if the person responded to
the vaccine. (6/26/03)
a new healthcare worker with a documented history of three doses
of hepatitis B vaccine did not have a serology test done, should
we test them when they start employment or do we wait until
they have an exposure.
1997, ACIP and the Hospital Infection Control Practices Advisory
Committee (HICPAC) published comprehensive recommendations for
the immunization of healthcare workers, ftp://ftp.cdc.gov/pub/Publications/mmwr/rr/rr4618.pdf.
One of the recommendations was that healthcare workers who have
contact with patients or blood and are at ongoing risk for injuries
with sharp instruments or needlesticks should be routinely tested
for antibody after vaccination. However, a catch-up program
of serologic testing for healthcare providers vaccinated prior
to December 1997 is not recommended. These individuals should
be tested if they have a significant exposure to HBV.
For employees in this situation who want to be sure of their
immune status, you could test them now. But be aware that if
they have no antibody, it could mean either that they failed
to respond to the vaccine series or that they responded and
their antibody level has fallen. We know this occurs in about
50% of people within 5 to 6 years after vaccination.
What we have recommended for situations in which no antibody
is detected is to give the person one dose of vaccine and test
again one month later. If the person responded to the original
series, this dose will stimulate the immune system to boost
their antibody and the test will be positive. Then simply document
the response; no additional doses of vaccine or further testing
If the person does NOT respond to this booster dose, we suggest
you complete a second series with two more doses of vaccine
and retest 4-6 weeks after the last dose. If there is a positive
response, document it and no further testing or vaccine doses
are needed. If the person does not respond after a second three-dose
series, considered him or her a non-responder and counsel accordingly.
At this point, if you have not already done so, you should test
for surface antigen (HBsAg). It is possible that they are not
responding to the vaccine because they are infected with the
hepatitis B virus.
postvaccination testing is not recommended for persons at low
risk of exposure, such as public safety workers and healthcare
workers without direct patient contact. (6/26/03)
an employee at our health services facility sustains a blood
exposure and has documented evidence of a positive hepatitis
B surface antibody (anti-HBs) response, do they require a booster?
a booster dose is not necessary. Please refer to Table 3, “Recommended
postexposure prophylaxis for percutaneous or permucosal exposure
to hepatitis B virus, United States” in the 1997 ACIP
recommendations for “Immunization of Health-Care Workers”,
our health-care workers have a documented positive antibody
response (anti-HBs) in the past, do we need to test them if
they sustain a blood exposure.
No, not if you have a documented positive antibody response
(>10 mIU/mL) following the 3-dose hepatitis B vaccine
(Table 3, page 23). (6/26/03)
is the recommendation for a healthcare worker who has been tested
for hepatitis B antibodies after three doses of vaccine and
the lab test shows no antibodies?
who do not respond to the first series of hepatitis B vaccine
should complete a second three-dose vaccine series. The second
vaccine series should be given on the usual 0, 1, 6-month schedule.
A 0, 1, 4-month accelerated schedule may also be used. Revaccinated
healthcare workers and others for whom postvaccination serologic
testing is recommended should be retested at the completion
of the second vaccine series.
than 5% of persons receiving 6 doses of hepatitis B vaccine
administered by the appropriate schedule in the deltoid muscle
fail to develop detectable anti-HBs antibody. Some persons who
are anti-HBs negative following 6 doses may have a low level
of antibody that is not detected by routine serologic testing.
One reason for persistent nonresponse to hepatitis B vaccine
is that the person is chronically infected with HBV. Persons
who fail to develop detectable anti-HBs after 6 doses should
be tested for HBsAg. Persons who are found to be HBsAg-positive
should be counseled accordingly. Vaccine non-responders who
are HBsAg-negative should be considered susceptible to HBV infection
and should be counseled regarding precautions to prevent HBV
infection and the need to obtain HBIG prophylaxis for any known
or probable parenteral exposure to HBsAg-positive blood, ftp://ftp.cdc.gov/pub/Publications/mmwr/rr/rr4618.pdf
(see page 23). (6/26/03)
give HIV+ patients a 4-dose series of hepatitis B vaccine (40
mcg) at 0, 1, 2, and 6 months. If they are anti-HBs negative
after the 4th dose, we give a 40 mcg booster at 12 months. If
they remain negative after this dose, what should we do?
best explanation for vaccination of hemodialysis patients and
other immunocompromised high-risk patients (e.g., HIV+) is in
the CDC “Recommendations for Preventing Transmission of
Infections Among Chronic Hemodialysis Patients”, http://www.cdc.gov/mmwr/PDF/rr/rr5005.pdf
(see pages 25-26).
primary schedule for the 40 mcg formulation of Engerix-B is
four doses at 0, 1, 2, and 6 months. (Recombivax-B uses a three-dose
schedule at 0, 1, and 6 months.) Vaccinees should be tested
for anti-HBs 1-2 months after the last primary dose to determine
their response to the vaccine (adequate = >10 mIU/mL).
If the response to the primary series is inadequate, then the
patient should be revaccinated with three additional
doses (regardless of which vaccine is used) and retested for
response. No additional doses of vaccine are warranted for those
who do not respond to the second series. (6/26/03)
hepatitis B surface antigen (HBsAg) detectable in the serum
after vaccination with the hepatitis B vaccine?
false positive reading for hepatitis B surface antigen can persist
for 3-4 weeks after a dose of hepatitis B vaccine. (6/26/03)