When symptoms are present, they may be mild or severe. The most common early symptoms are mild fever, headache, muscle aches, fatigue, loss of appetite, nausea, vomiting, or diarrhea. Early signs of fulminant hepatitis, such as personality changes and agitated behavior, require immediate medical attention. Some people infected with HBV or HCV become chronic carriers of the virus, although they may have no symptoms. There are an estimated 1.5 million HBV carriers in the U.S. and 300 million carriers worldwide.
Children are at greatest risk.
About 90 percent of babies who become infected at birth with HBV, and up to half of youngsters who are infected before age 5, become chronic carriers. It is estimated that there are between 2 and 5 million HCV chronic carriers. At least half of all HCV carriers will develop chronic liver disease, regardless of whether or not they have symptoms. Diagnosis Hepatitis B. Several types of blood tests can detect signs of HBV even before symptoms develop. Most people with acute hepatitis B have HBsAg in their blood before symptoms develop.