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

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 Prevention Atlanta, GA

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

Natural History of Hepatitis B Virus (HBV) Infection Although substantial progress has been made in implementing hepatitis B vaccination programs, hepatitis B continues to be a major public health problem in the United States. In 2003 - estimated According to data from NHANES

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)

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)

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%

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! How do we prevent HBV infections in infancy and early childhood? There are 2 major modes of HBV transmission in infancy and early childhood: vertical transmission from an infected mother to her infant and horizontal transmission from an infected household contact to the child. Importantly, both modes of transmission can be prevented by vaccination of newborns. Let us examine each of these modes of transmission more closely.

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 not transmitted by breastfeeding Vertical transmission of infection from mother to infant, generally occurs as a result of percutaneous and permucosal exposure to the mother’s infected blood during birth. In utero transmission of HBV is rare, accounting for <2% of all perinatal infections. Although HBV is found in low concentrations in breast milk, it has not been documented to be transmitted through breastfeeding.

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

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

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

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

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 1st bullet: Health department determines the pregnancy status

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

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

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

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

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 Can we talk about how to keep the list of labs—working with CD?

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 Not sure if you want the photo or not… More on laboratory evaluations in Session 3 of this series

Develop Protocols To successfully identify cases, HBV prevention activities should be implemented by: perinatal program health department delivery hospitals universal reporting prenatal care providers Does this photo work or not?

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 The IPOM does refer to it as a “protocol for perinatal hepatitis B prevention”

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

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

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 More info on working with delivery hospitals will be presented in sessions 3 and 4… Health department should monitor these activities More on delivery hospital evaluations in Session 4 of this series

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

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

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