Fewer than half of people living with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) are aware of their status, which means they are not getting treatment and have an ongoing risk of transmission to others, according to a recent study.
HBV and HCV are spread through contact with blood, sexual transmission and vertical transmission from mother to child. HBV can be prevented with a vaccine and treated with antiviral drugs, but it is rarely cured. There is not yet a vaccine for HCV, but new direct-acting antivirals can cure most people with the virus.
But before they can be treated, people with HBV or HCV (or both) must be tested to determine whether they carry the viruses and then be linked to care. Over years or decades, hepatitis B and C can cause liver cirrhosis (severe scarring), liver cancer and liver failure that may require a transplant. But both diseases often have no symptoms at early stages, and many people do not suspect they have one of the viruses until they reach advanced stages of disease.
As described in Clinical Gastroenterology and Hepatology, researchers Kali Zhou, MD, of the University of California, San Francisco, and Norah Terrault, MD, of the University of Southern California in Los Angeles, aimed to identify gaps in awareness of hepatitis B or C among adults in the United States using data from the National Health and Nutrition Examinations Surveys.
This study included 14,745 participants age 20 or older who were surveyed between 2013 and 2016 and had available blood test results. They were asked, “Has a doctor or other health professional ever told you that you have hepatitis B or C?”
HBV infection was defined as detection of hepatitis B surface antigen (HBsAg); people who clear the virus naturally or with treatment test negative for this antigen. HCV infection was defined as detection of antibodies against the virus; people who clear HCV naturally or are cured with treatment generally still carry these antibodies.
The researchers reported that 68 participants tested positive for HBV, for a prevalence of 0.7%, while 211 tested positive for HCV, a prevalence of 1.8%.
Among participants who tested positive for HBV, 32% reported that they were aware of their status; 28% of those who were aware reported receiving treatment. Among those who tested positive for HCV, 49% were aware, 45% of those who were aware were treated and 59% of those who were treated achieved sustained virological response, considered a cure. This rate is low compared with direct-acting antiviral cure rates in clinical trials, and some may have been treated with the older, less effective interferon-based therapy.
Factors associated with greater awareness of HBV infection included U.S. citizenship, higher education and an abnormal alanine aminotransferase (ALT) liver enzyme level. Factors associated with HCV awareness were income above the poverty level, not being married and a history of injection drug use; Latino people were less likely to be aware they had HCV.
“Fewer than half of U.S. adults with HBV or HCV infection are aware of their infection,” the study authors concluded. They added that opportunities to increase awareness include educating providers about abnormal ALT values that should prompt screening and expansion of screening interventions to underrecognized risk groups. For example, immigrants, especially those from Asia, have a high HBV rate, and they may be less likely to undergo screening and receive educational information in their preferred language.
Click here to read the study abstract.