If a patient with HBV develops flare-ups of symptoms weeks after onset, or after initial symptoms have receded, then the patient is said to have chronic HBV. Chronic HBV occurs when the virus enters an inactive state but then reactivates, with renewed viral replication and renewal of disease activity.
For patients with chronic HBV, reactivation can occur without any obvious cause or trigger. Some of the patient populations that are at a higher risk for HBV reactivation include:
- Those with HCV
- Those undergoing a bone marrow transplant
- Those undergoing a solid organ transplant
- Those with HIV who do not take HBV antiviral drugs
- Those taking immunosuppressive therapy
The chances of an HBV infection becoming chronic is highest among young children. Around 90% of infants and 25% to 50% of children aged 1 to 5 who are infected with HBV will develop chronic HBV. These rates are much lower for adults. Only 5% of adults who contract HBV will develop a chronic infection.
Around 25% of those chronically infected during childhood and 15% of those chronically infected as adults, end up dying prematurely. This is usually due to cirrhosis or liver cancer, which are typically preceded by few if any symptoms. The age-adjusted hepatitis B-related mortality rate in the US decreased from 0.46 per 100,000 population in 2017 to 0.42 in 2019. However, the rates of acute hepatitis B infection have risen 50%-450% in states impacted by the opioid crisis.
