The Essentials of Perinatal Hepatitis B Prevention

1. The Essentials of Perinatal Hepatitis B Prevention A Training Series for Coordinators and Case Managers

2. Session 1: Case Identification Dr. Susan Wang Medical Officer Division of Viral Hepatitis National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention Centers for Disease Control and PreventionAtlanta, GA

3. Learning Objectives At the end of the session…. • Describe key components of case identification in a perinatal hepatitis B prevention program • methods for improving identification of hepatitis B virus infected pregnant women and infants at risk

4. Natural History of Hepatitis B Virus (HBV) Infection

5. Hepatitis B in the U.S. • 1 in 200 persons have chronic HBV infection (about 1.25 million) • About 60,000 new infections in 2004 (200,000-300,000 annually before vaccination programs) • 4,000-5,000 deaths annually from hepatitis B-related chronic liver disease (cirrhosis, liver cancer)

6. Perinatal Hepatitis B in the U.S. • About 24,000 infants were born to HBV-infected mothers in 2005 • Without immunoprophylaxis (vaccine and hepatitis B immune globulin [HBIG]): • about 9,100 chronically infected with HBV (most asymptomatic) • about 2,300 expected to die of chronic liver disease (cirrhosis or liver cancer)

7. Risk of Chronic HBV Infection • Very dependent on age when infection is acquired • Among infected children, symptomatic acute hepatitis B rare; likelihood of developing chronic infection high: Age at infection <1 year 1-5 years >5 years Risk of acute HBV <1% 5%-15% 20%-50% Risk of chronic HBV 90% 25%-50% 6%-10%

8. Modes of HBV Transmission in Infancy and Early Childhood • Transmission from infected mother to neonate during delivery • Transmission from infected household contact to child • Both modes of transmission can be prevented by vaccination of newborns!

9. Maternal to Child HBV Transmission • Percutaneous and permucosal exposure to mother’s blood during birth • In utero transmission rare: accounts for <2% of perinatal infections • HBV nottransmitted by breastfeeding

10. Prevention of HBV Transmission • Post-exposure prophylaxis is highly effective in preventing HBV transmission after exposure: • when given within 24 hours of birth, hepatitis B vaccine and HBIG* is 85%-95% effective • hepatitis B vaccine alone at birth is 70%-95% effective *Hepatitis B Immune Globulin

11. Hepatitis B Vaccine: Two Purposes • Administered at birth to an infant born to an HBV-infected mother, hepatitis B vaccine serves as post-exposure prophylaxis • Administered at birth to an infant born to an uninfected mother, hepatitis B vaccine serves as pre-exposure protection

12. Prenatal HBsAg* Testing • All pregnant women should be tested during each pregnancy • best in early pregnancy • women not tested prenatally should be tested at delivery • high risk women^ should be retested at delivery *Hepatitis B Surface Antigen ^Women with >1 sex partner in past six months, evaluation/treatment for STD, history of IDU, or HBsAg-positive sex partner

13. Perinatal Case Identification Delivering women tested for HBsAg at hospital (if not tested previously) Women tested for HBsAg prenatally HBsAg+ test results reported to health department Health department determines pregnancy status for reports of HBsAg+ women Pregnant women/infants identified for case management

14. Methods of Identification • Laboratories report HBsAg+ results, pregnancy status is determined • Prenatal care providers report cases • HBsAg+ women self report • Hospitals report cases • Universal reporting mechanisms (birth certificate, newborn screening) detect cases retrospectively

15. Expected Births to HBsAg+ Women • CDC calculates expected births to HBsAg+ women annually using NHANES* and vital statistics birth data • About 50% of the expected 24,000 infants are identified by health departments for case management annually *National Health and Nutrition Examination Survey

16. Identified vs Expected Births to HBsAg+ Women, U.S., 1993–2004 23,919 Expected births 19,043 50% 41% Identified births Source: National Center for Immunization and Respiratory Diseases, CDC

17. Gaps in Identification • Laboratory reporting often only source used and incomplete • Overwhelming volume of HBsAg test results to review for pregnancy status • Some pregnant women not tested or reported by providers • women known to be HBsAg-positive • no prenatal care (~ 5%) • Many hospitals do not report cases

18. Methods to Improve Identification • Verify all laboratories are reporting all HBsAg-positive results • Review by health department of all HBsAg-positive reports • Monitor to ensure delivery hospitals are testing and reporting • Establish universal reporting mechanisms • Remind prenatal care providers to screen and report

19. Evaluate Laboratory Reporting • Keep a list of laboratories that conduct HBsAg testing • Ensure laboratories are regularly reporting cases to the health dept • Collaborate with communicable disease program to conduct laboratory evaluations and measure: • completeness of HBsAg reporting • timeliness of HBsAg reporting

20. Prioritizing Laboratories to Evaluate • Priority laboratories: • labs serving high-morbidity areas or populations • labs reporting large volumes of hepatitis serology • labs serving prenatal clinics • delivery hospital labs • How often? • ideally, once/year for priority laboratories • every 2–3 years for other laboratories More on laboratory evaluations in Session 3 of this series

21. Develop Protocols • To successfully identify cases, HBV prevention activities should be implemented by: • perinatal program • health department • delivery hospitals • universal reporting • prenatal care providers

22. Perinatal Prevention Protocol • Describes perinatal HBV prevention activities and outlines responsibilities of all parties: • laboratories pediatricians • delivery hospitals health departments • prenatal care providers • Required by immunization grant to disseminate annually to partners

23. Perinatal Prevention Protocol (cont’d) • Examples available at CDC’s Perinatal Hepatitis B Coordinator website: http://www.cdc.gov/ncidod/diseases/ hepatitis/resource/perinatalhepB.htm

24. Case Identification Protocols • Health departments should have protocols in place to: • review all HBsAg-positive reports • identify results for all women of childbearing age • determine pregnancy status of those women • review reports in a timely manner

25. Delivery Hospital Policies • Hospitals should have policies and practices to test unknown status or high risk women for HBsAg at delivery • Hospital laboratories, obstetrics, and nurseries have policies to report HBsAg+ delivering women • Health department should • monitor these activities More on delivery hospital evaluations in Session 4 of this series

26. Universal Reporting Mechanisms • Include maternal HBsAg status on: • electronic birth certificate (EBC) or • newborn metabolic screening (NBS) card • Gain access to these data on a regular basis to identify cases retrospectively • Work with Vital Statistics to educate hospital staff on properly completing EBC forms and with Newborn Screening staff to properly complete NBS forms

27. Prenatal Care Provider Practice • Screen all pregnant women for HBsAg • Report HBsAg-positive pregnant women • Health department should monitor • that providers report

28. For More Detail Chapter 1 of CDC’s Managing a Perinatal Hepatitis B Prevention Program: Guide to Life as a Program Coordinator http://www.cdc.gov/ncidod/diseases/ hepatitis/resource/perinatalhepB.htm