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Hepatitis B Infection
Transmission
Hepatitis B virus (HBV) is a double-stranded DNA virus in the Hepadnaviridae
family.
The incubation period from time of exposure to onset of symptoms is 6 weeks
to 6 months. HBV is found in highest concentrations in the blood, and lower
concentrations in semen, vaginal secretions, and wound exudates. Sexual
transmission accounts for most adult HBV infections in the United States [1].
Approximately 25% of the regular sexual contacts of infected individuals will
themselves become seropositive. [2]
About one half of acute HBV infections are symptomatic in adults with 1% of
cases resulting in acute liver failure and death. Acutely infected individuals
develop clinically apparent acute hepatitis with loss of appetite, nausea,
vomiting, fever, abdominal pain and jaundice [1]. 10-20% of women seropositive for HBsAg transmit the virus to their neonates
in the absence of immunoprophylaxis. In women who are seropositive for both
HBsAg and HBeAg vertical transmission is approximately 90% [2]. In patients with acute hepatitis B vertical transmission occurs in up to 10%
of neonates when infection occurs in the first trimester and in 80 -90% of
neonates when acute infection occurs in the third trimester [2].
Sequelae
Chronic infection occurs in about 90% of infected infants, 60% of infected
children aged <5 years , and 2%--6% of adults. Among persons with chronic HBV
infection, the risk of death from cirrhosis or hepatocellular carcinoma is
15%--25%. [1]
HBV infection does not appear to be teratogenic [3]. However, there appears
to be a higher incidence of low birth weight among infants born to mothers with
acute infection during pregnancy [3]. In one small study acute maternal hepatitis (type B or nontype B) had no
effect on the incidence of congenital malformations, stillbirths, abortions, or
intrauterine malnutrition. However, acute hepatitis did increase the incidence
of prematurity [4].
Who to test [1]
- Test all pregnant women at the first prenatal visit for hepatitis B surface
antigen (HBsAg).
- Women admitted for delivery who have not had prenatal HBsAg testing should
have blood drawn for testing [5].
- Send a copy of the original lab report to the hospital.
- “More than 90% of women found to be HBsAg-positive on routine screening will
be HBV carriers, routine follow-up testing later in pregnancy is not necessary
for the purpose of screening. In special situations, such as when the mother is
thought to have acute hepatitis, when there has been a history of exposure to
hepatitis, or when particularly high-risk behavior such as parenteral drug abuse
has occurred during the pregnancy, an additional HBsAg test can be ordered
during the third trimester” [6]
- Test all susceptible contacts (including all family members) with hepatitis B
panel (HBsAg, antiHBc, antiHBs).
- Screening and vaccination of susceptible contacts should be done by the
family's pediatrician, primary health-care provider, or the physician evaluating
the clinical status of the HBsAg-positive pregnant women.
Interpretation of the Hepatitis B Panel
Tests Results Interpretation
|
Tests |
Results |
Interpretation |
|
HBsAg
anti-HBc
anti-HBs |
negative
negative
negative |
susceptible
|
|
HBsAg
anti-HBc
anti-HBs |
negative
positive
positive |
immune due to natural infection
|
|
HBsAg
anti-HBc
anti-HBs |
negative
negative
positive |
immune due to hepatitis B vaccination |
|
HBsAg
anti-HBc
IgM anti-HBc
anti-HBs |
positive
positive
positive
negative |
acutely
infected
|
|
HBsAg
anti-HBc
IgM anti-HBc
anti-HBs |
positive
positive
negative
negative |
chronically
infected
|
|
HBsAg
anti-HBc
anti-HBs |
negative
positive
negative |
four
interpretations
possible * |
|
* 1. May be recovering
from acute HBV infection.
2. May be distantly immune and test not sensitive enough to to detect
very
low level of anti-HBs
in serum.
3. May be susceptible with a false positive anti-HBc.
4. May be undetectable level of HBsAg present in the serum and the
person is actually a
carrier.
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Source:
http://www.cdc.gov/ncidod/diseases/hepatitis/b/Bserology.htm
A positive HBsAg in the absence of IgM anti-HBc is indicative of chronic
infection.If positive, this test result should be reported to state perinatal
immunization or HBV prevention programs to ensure proper case management of the
mother and appropriate postexposure immunization of her at-risk infant [1]. The baby's health-care provider should be notified about the mother's HBsAg-positive
status and receive hepatitis B immune globulin (HBIG) and HBV vaccine.
Treatment
The treatment of acute HBV infection is supportive.Persons with chronic hepatitis B should be referred to health-care
professionals with experience in the treatment of hepatitis B for treatment with
alpha-interferon or lamivudine [1]. Interferon does not appear to adversely affect the embryo or fetus. However,
the data is limited, and the potential benefits of interferon use during
pregnancy should clearly outweigh possible hazards [7-9]. Initial data do not suggest that Lamivudine is teratogenic [10]. Lamivudine
has been used in the latter half of pregnancy in attempt to prevent perinatal
transmission of hepatitis B virus infection with mixed success [11,12]
Postexposure Prophylaxis for Susceptible Pregnant Women [1, 13]
Exposure to Persons Who Have Acute Hepatitis B
When exposure has occurred as a result of sexual contact within 14 days after
the most recent sexual contact administer
A course of HBV vaccine into the deltoid
- The two available monovalent hepatitis B vaccines for preexposure immunization
and postexposure prophylaxis are Recombivax HB® (Merck and Co., Inc.) and
Engerix-B (SmithKline Beecham Biologicals).
A dose of Hepatitis B immune globulin (HBIG) 0.06 mL/kg IM into the
contralateral arm.
- For prophylaxis after percutaneous or mucous membrane injury, a second dose of
HBIG should be given 1 month later.
Exposure to Persons Who Have Chronic HBV Infection
Active postexposure prophylaxis with hepatitis B vaccine alone is recommended
for sex or needle-sharing partners and non-sexual household contacts of persons
with chronic HBV infection
Other Candidates for Vacination
• Household contacts and sex partners of HBsAg-positive women identified through
prenatal screening should be vaccinated [5] .
• Persons with history of an STD.
• Persons on hemodialysis, persons receiving clotting factor concentrates, or
persons who have occupational exposure to blood.
• All persons who have not been previously vaccinated who receive services in
drug treatment programs and long-term correctional facilities
• Pregnant women seeking STI treatment who have not been previously vaccinated
and test negative for hepatitis B, should receive the hepatitis B vaccine.
Antepartum
Pregnant Hepatitis B carriers should be advised to
• Obtain vaccination against hepatitis viruses A as indicated.
• Abstain form alcohol use
• Avoid hepatotoxic drugs such as acetaminophen (Tylenol) that may worsen liver
damage.
• Not donate blood, body organs, other tissue, or semen.
• Not share any personal items that may have blood on them (e.g., toothbrushes
and razors).
• Inform the infant’s pediatrician, OB/GYN, and labor staff that they are a
hepatitis B carrier.
• Make sure their baby receives hepatitis B vaccine at birth, one month, and six
months of age as well as H-BIG at birth.
• Be seen at least annualy by their regular medical doctor.
• Discuss the risk for transmission with their partner and discuss the need for
counseling and testing
b. Liver function testing is recommended for women who test positive for HBsAg
[1]
The following recommendations from The Society of Obstetricians and
Gynecologists of Canada may be helpful in counseling women considering
amniocentesis.
SOGC Recommendations [14]
• “The risk of fetal hepatitis B infection through amniocentesis is low.
However, knowledge of the maternal hepatitis B e antigen status is valuable in
the counselling of risks associated with amniocentesis.
• For women infected with hepatitis B, hepatitis C, or HIV, the addition of
noninvasive methods of prenatal risk screening, such as nuchal translucency,
triple screening, and anatomic ultrasound, may help in reducing the age-related
risk to a level below the threshold for genetic amniocentesis.
• For those women infected with hepatitis B, hepatitis C, or HIV who insist on
amniocentesis, every effort should be made to avoid inserting the needle through
the placenta. “
Delivery
Although cesarean delivery has been proposed as a means of reducing mother to
child transmission (MCT) of HBV [15] The mode of delivery does not appear to
have a significant effect on the interruption of HBV maternal-baby transmission
by immunoprophylaxis [16]. Delivery by cesarean section for the purpose of
reducing MCT of HBV is note presently recommended by either the CDC [1] or the
ACOG [2].
Breast feeding.
With appropriate hepatitis B immunoprophylaxis, breast-feeding poses no
additional risk for transmission from infected hepatitis B virus carriers
[17,18]
REFERENCES:
1. Centers for Disease Control and Prevention Sexually Transmitted
Diseases Treatment Guidelines --- 2002 .MMWR May 10, 2002 / 51(RR06);1-80
2. ACOG educational bulletin. Viral hepatitis in pregnancy. Number 248, July
1998 . American College of Obstetricians and Gynecologists. Int J Gynaecol
Obstet. 1998 ;63:195-202.
MEDLINE
3. Shepard TH. Catalog of Teratogenic Agents pp 1309. 9th ed.Baltimore, MD:
Johns Hopkins University Press,
1998 .p1309
4. Hieber JP, Dalton D, Shorey J, Combes B.Hepatitis and pregnancy.J
Pediatr. 1977 Oct;91(4):545-9.
MEDLINE
5. Hepatitis B Virus: A Comprehensive Strategy for Eliminating Transmission
in the United States Through Universal Childhood Vaccination:
Recommendations of the Immunization Practices Advisory Committee (ACIP) MMWR
November 22, 1991 / 40(RR-13);1-19
6. Recommendations of the Immunization Practices Advisory Committee
Prevention of Perinatal Transmission of Hepatitis B Virus: Prenatal
Screening of all Pregnant Women for Hepatitis B Surface Antigen MMWR June
10, 1988 / 37(22);341-6,351
7. Briggs GG,Freeman RK, Yaffe SJ, Drugs in Pregnancy and Lactation 5th
edition,Baltimore, MD:
Williams & Wilkins,1998 p 716-720.
8. Ozaslan E, Yilmaz R, Simsek H, Tatar G. Interferon therapy for acute
hepatitis C during pregnancy.
Ann Pharmacother. 2002;36:1715-8.
MEDLINE
9. Hiratsuka M, Minakami H, Koshizuka S, Sato I. Administration of
interferon-alpha during pregnancy: effects on fetus. J Perinat Med.
2000;28(5):372-6.
MEDLINE
10. Briggs GG,Freeman RK, Yaffe SJ, Drugs in Pregnancy and Lactation 5th
edition,Baltimore, MD: Williams & Wilkins,1998 p 761-766.
11. van Zonneveld M, van Nunen AB, Niesters HG, de Man RA, Schalm SW,
Janssen HL. Lamivudine treatment during pregnancy to prevent perinatal
transmission of hepatitis B virus infection.J Viral Hepat. 2003 ;10(4):294-7.
MEDLINE
12. Kazim SN, Wakil SM, Khan LA, Hasnain SE, Sarin SK. Vertical transmission
of hepatitis B virus despite maternal lamivudine therapy. Lancet.
2002;359(9316):1488-9
MEDLINE
13. Centers for Disease Control. Protection against viral hepatitis.
Recommendations of the Immunization Practices Advisory Committee (ACIP).
MMWR 1990;39(RR-2):1-26
14. Davies G et al Society of Obstetricians and Gynaecologists of Canada.
Amniocentesis and women with hepatitis B, hepatitis C, or human
immunodeficiency virus. J Obstet Gynaecol Can. 2003 ;25(2):145-48, 149-52.
MEDLINE
15. Lee SD, Lo KJ, Tsai YT, Wu JC, Wu TC, Yang ZL, Ng HT. The role of
cesarean section in the prevention of mother-infant transmission of hepatitis B
virus. Lancet. 1988;2:833-4.
MEDLINE
16. Wang J, Zhu Q, Zhang X. Effect of delivery mode on maternal-infant
transmission of hepatitis B virus by immunoprophylaxis. Chin Med J (Engl)
2002 Oct;115(10):1510-2
MEDLINE
17. Hill JB et al , Risk of hepatitis B transmission in breast-fed infants
of chronic hepatitis B carriers.
Obstet Gynecol. 2002 ;99(6):1049-52.
MEDLINE
18. Wang JS, Zhu QR, Wang XH. Breastfeeding does not pose any additional
risk of immunoprophylaxis failure on infants of HBV carrier mothers. Int J
Clin Pract. 2003 ;57(2):100-2.
MEDLINE ADDITIONAL READING:
Hepatitis B infection in pregnancy
1999 Contemporary OB/GYN
Hepatitis
Center for Disease Control and Prevention
Created: 12/10/2000
Last update: 11/30/2003
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