Hepatitis B Virus Infection: Current Trends in Host-Pathogen Interaction, Diagnosis, & Treatment

Hepatitis B virus (HBV) is a significant and widespread human pathogen primarily targeting hepatocytes, resulting in severe liver illnesses. Despite the presence of a potent vaccine against HBV, there are still over 250 million chronic infections globally. HBV is an enveloped partially double-stranded DNA virus. The transmission of HBV can occur through percutaneous or mucosal exposure to infected bodily fluids, and it can remain viable on environmental surfaces for more than 7 days. Clinical manifestations of HBV infection vary between acute and chronic diseases. Acute infection may present as icteric hepatitis, subclinical or anicteric hepatitis, or rarely, fulminant hepatitis, while chronic infection may lead to an asymptomatic carrier state, cirrhosis, and hepatocellular carcinoma (HCC). Preliminary indications are nonspecific and may include nausea, vomiting, anorexia, and abdominal pain. Suppose in severe liver damage, patients can progress to jaundice, ascites, hepatic encephalopathy, gastrointestinal bleeding secondary to oesophageal varices, or coagulopathy. The primary objective of the proposed chapter is to confer HBV structural and molecular organization, life cycle, pathogenesis, and the available therapeutic interventions for HBV.