The presence of antibodies to the surface antigen, which are considered to be a marker of immunity, does not preclude reactivation. Treatment with prophylactic antiviral drugs can prevent the serious morbidity associated with HBV disease reactivation. Epidemiology
At least 296 million people, or 3.8% of the worlds population, had chronic HBV infection as of 2019. Another 1.5 million cases of acute HBV infection also occurred that year. Regional prevalences across the globe range from around 7.5% in Africa to 0.5% in the Americas.The primary method of HBV transmission and the prevalence of chronic HBV infection in specific regions often correspond with one another. In populations where HBV infection rates are 8% or higher, which are classified as high prevalence, vertical transmission (usually occurring during birth) is most common, though rates of early childhood transmission can also be significant among these populations. In 2021, 19 African countries had infection rates ranging between 8-19%, placing them in the high prevalence category.In moderate prevalence areas where 2–7% of the population is chronically infected, the disease is predominantly spread horizontally, often among children, or vertically. China’s HBV infection rate is at the higher end of the moderate prevalence classification with an infection rate of 6.89% as of 2019. HBV prevalence in India is also moderate, with studies placing India’s infection rate between 2-4%.Countries with low HBV prevalence include Australia (0.9%), those in the WHO European Region (which average 1.5%), and most countries in North and South America (which average 0.28%).
To further prevent infection, the WHO recommends testing all donated blood for hepatitis B before using it for transfusion. Using antiviral prophylaxis to prevent mother-to-child transmission is also recommended, as is following safe sex practices, including the use of condoms In 2016, the WHO set a goal of eliminating viral hepatitis as a threat to global public health by 2030. Achieving this goal would require the development of therapeutic treatments to cure chronic hepatitis B, as well as preventing its transmission and using vaccines to prevent new infections.An estimated 296 million people, or 3.8% of the global population, had chronic hepatitis B infections as of 2019. Another 1.5 million developed acute infections that year, and 820,000 deaths occurred as a result of HBV. Cirrhosis and liver cancer are responsible for most HBV-related deaths. The disease is most prevalent in Africa (affecting 7.5% of the continent’s population) and in the Western Pacific region (5.9%). Infection rates are 1.5% in Europe and 0.5% in the Americas. According to some estimates, about a third of the worlds population has been infected with hepatitis B at one point in their lives. Hepatitis B was originally known as "serum hepatitis". Signs and symptoms
Acute infection with hepatitis B virus is associated with acute viral hepatitis, an illness that begins with general ill-health, loss of appetite, nausea, vomiting, body aches, mild fever, and dark urine, and then progresses to development of jaundice. The illness lasts for a few weeks and then gradually improves in most affected people.