Hepatitis B is a viral infection of the liver characterized by loss of appetite, body malaise, fatigue, weakness, fever, joint pains, dark colored urine and stool, pain in the abdomen and nausea and vomiting. Outward manifestations of the disease include yellowing of the skin and the whites of the eyes, also known as jaundice. Within 6 months of infection, inflammation of the liver often occurs, accompanied by scarring and significant damage to other vital organs. Cirrhosis more likely develops in patients who are older than 40 years old, while others have increased risks for liver cancer, HIV, and Hepatitis C.
In regions where Hepatitis B is endemic, the virus is most often spread via perinatal transmission, that is when a mother gives birth to her child, in which case a chronic infection occurs. Horizontal transmission, or that through infected blood exposure, can also happen, especially between children who are five years old and younger. Other means of transmission are via contact with the bodily fluids of infected people, such as through the use of contaminated needles and syringes, as well as unprotected sexual activity with multiple partners. The virus is quite resilient, in that it is able to survive outside the human body for up to one week, at which time it can still infect people if transmitted into the blood stream of an unvaccinated person. Its normal incubation period is 75 days, but may vary between 30 and 180 days.
Acute Hepatitis B has no treatment, so care is mainly administered to provide comfort for the patient, whereas Chronic Hepatitis B is treatable with the use of oral antiviral drugs, among others. At present, no less than 780,000 patients succumb to the complications brought about by Chronic Hepatitis B, such as liver cancer, HIV, and liver cirrhosis. In the US, no less than 1.4 million people are Hepatitis B carriers, meaning they can, and often do, infect other people via sexual contact, sharing of needles and syringes, or other means.
The greatest rates of Hepatitis B cases have been reported in East Asia and sub-Saharan Africa, where at least 5% of some countries' population are diagnosed as having the chronic infection. Similar figures have also been reported in the Amazon Region, as well as many countries located in in Central and Southern Europe. The Indian subcontinent and the Middle East have also reported that 2% to 5% of their countries' adult populations are infected chronically. Meanwhile, no more than 1% are infected in the Northern and Eastern parts of the United States.
The World Health Organization (WHO) endorses the use of oral drugs, such as entecavir and tenofovir, among patients who have been diagnosed with chronic hepatitis B infections. These two are recognized as being the most effective in suppressing the virus and, to date, very few cases of drug resistance have been reported. Most importantly, they are among the easiest to administer, wherein one oral pill per day is often all it takes to keep the virus under control. Side effects are also very few and far between, something that is often the issue in most drugs currently being used for serious illnesses.