![]() 5 Those particles now are known to represent incomplete portions of the viral envelope, synthesized in great excess during the process of virus replication. 4 Subsequent work by Blumberg's group and others established a link between the newly identified antigen and acute hepatitis B, an association confirmed by electron microscopy identification of particles dense with the antigen in the serum of patients who were acutely ill with hepatitis. Later found to be present in the serum of institutionalized patients, it was even believed to be possibly associated with Down syndrome. The antigen, first isolated in the serum of an Australian aborigine during a study of serum protein polymorphisms (hence its being labeled the “Australia antigen”), 3 was found incidentally to cross-react with the serum of multiply transfused patients. ![]() Discovered by Blumberg and co-workers in 1965, 2 it initially was not known to be a virus-associated marker. Hepatitis B surface antigen (HBsAg) is the HBV serum marker that has come to be used most commonly in clinical situations and screening protocols. Not surprisingly, these concerns are directly applicable to determining relative risks for vertical (maternal–fetal) transmission of the virus. Much attention has been paid to the use of HBV-specific markers in serum to distinguish active from previous infection and to determine the relative infectiousness of a particular individual. 1 Using its own DNA polymerase for replication, the virus is able to reproduce within a host's infected hepatocytes, drawing from the cell's pool of nucleotide precursors. HBV is a small (42-nm) DNA virus that contains partially double-stranded DNA within its core. Widespread adoption of such approaches, combined with ongoing HBV vaccination protocols in high-risk populations, including medical personnel, will make significant inroads against the overall prevalence of HBV-related disease.Īlthough an exhaustive discussion of HBV biology is beyond the scope of this chapter, an understanding of the basic structures and serologic tests associated with the virus is essential to understanding the logistics of perinatal transmission and prevention. This section outlines the evidence supporting antenatal identification of HBV-carrier mothers and targeted HBV immunoprophylaxis in their newborn children. ![]() Perinatal transmission of HBV from mothers with chronic infection to their at-risk neonates remains a significant route for the perpetuation of the HBV carrier state, with its concomitant health risks, worldwide. Project HOPE-The People-to-People Health Foundation, Inc.Our evolving understanding of the immunology of the hepatitis B virus (HBV) has led to the development of safe and effective therapies for preexposure and postexposure virus-specific prophylaxis. An intermediate scenario-treating 5 percent of the infected population annually, regardless of patients' disease stages-would also return substantial benefits and would be much more affordable under current financing schemes.Īccess To Care Epidemiology Health Economics Health Promotion/Disease Prevention Health Spending. Treating patients at all disease stages could generate $610-$1,221 billion in additional quality-adjusted life-years, plus an additional $139 billion in saved medical expenditures over fifty years, and minimize the disease burden, but up-front treatment costs would exceed $150 billion. To quantify the benefit of these treatments to society, including the value of reduced transmission, we estimated the effects of several hepatitis C treatment strategies on cost and population health. These treatments could dramatically reduce the virus's prevalence but are costly. Recent innovations have produced breakthrough therapies that are effective in more than 90 percent of patients. Treatment of hepatitis C virus, the most common chronic viral infection in the United States, has historically suffered from challenges including serious side effects, low efficacy, and ongoing transmission and reinfection.
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