Once again, the U.S. Preventive Services Task Force (USPSTF) has strongly backed routine testing of all pregnant women for hepatitis B. The USPSTF updated its recommendation statement on testing on July 23 with an article in the Journal of the American Medical Association.
The statement on hepatitis B gives a grade A recommendation -- meaning the task force has high confidence in the evidence -- for routine screening with the hepatitis B surface antigen (HBsAg) test for all pregnant women. Ideally, testing should be performed in the first trimester, but it should at least be done in an early prenatal visit, according to Stanford University health policy expert Dr. Douglas Owens and colleagues on the task force (JAMA, July 23/30, 2019, Vol. 322:4, pp. 349-354).
The support is in line with the previous grade A recommendation for routine hepatitis B virus (HBV) screening for all pregnant women in the last statement on the topic, which was released in 2009, as well as an even earlier report in 1996. For the latest report, the USPSTF used a reaffirmation deliberation process.
"The USPSTF found limited evidence on the harms of screening for HBV infection in pregnant women but bounded the potential harms of screening as no greater than small based on the high accuracy of screening and the low likelihood of harms from preventive interventions," the group explained in JAMA.
Routine hepatitis B screening is required by law in 26 states in the U.S., the authors noted. Those who test positive may be treated with tenofovir (Viread, Gilead) antiviral therapy to prevent transmission of the infection from mothers to their children. In cases where the infection has been transmitted, newborns may be treated with hepatitis B immune globulin.
Room to improve on screening
Hepatitis B leads to chronic liver disease in 30% to 90% of cases, noted Dr. Neil Silverman, an ob/gyn at the Center for Fetal Medicine and Women's Ultrasound at the University of California, Los Angeles, in an accompanying editorial. Thanks to vaccination, the rate of HBV infection in the U.S. dropped from 10 cases per 100,000 population in 1982 to 1.1 cases per 100,000 population in 2015 -- an 89% decline -- though it plateaued after 2010 and the actual rates are thought be higher than reported cases.
There is still room for improvement in screening, however, as it is estimated that only 84% to 88% of pregnant women in the U.S. are screened before delivery, Silverman wrote.
In addition to general screening for hepatitis B, it is important to determine the maternal viral load to assess treatment with antiviral therapy during pregnancy. A "number of national scientific and professional organizations in the United States and Europe have added a recommendation for viral load screening early in pregnancy in women known to be or diagnosed as HBV-infected through routine screening, using HBsAg as the marker of infection," he wrote. Therapy is recommended for pregnant women who have a viral level above 200,0000 IU/mL, as this is associated with an increased risk for fetal intrauterine infection.
Hepatitis testing is a $3.3 billion market worldwide, according to a market research report on diagnostics for infectious diseases from Kalorama Information, a sister company of LabPulse.com. In 2018, 38 million cases were diagnosed globally, bringing the total number of chronically infected people up to 366 million, with more than 80% of new cases and 85% of deaths in developing countries.
IVD products for hepatitis testing include immunoassays, which are used to detect specific viral pathogens, and molecular testing applications, which are designed to boost sensitivity and selectivity as well as measure viral load.