The hepatitis B virus (HBV) affects the liver and can cause acute or chronic illness. The virus’s life cycle involves entering liver cells and producing new virus cells to trigger infections in other liver cells.
Hepatitis B is a serious infection that targets the liver. It causes symptoms that can include abdominal pain, tiredness, and fever. The disease can become chronic and lead to permanent damage, which may result in serious complications.
There are several types of hepatitis, ranging from hepatitis A to E. The virus responsible for hepatitis B is HBV. This virus can transmit through blood, semen, and other bodily fluids from someone with the infection to another individual.
The life cycle of HBV involves entering liver cells, where the virus replicates and then attempts to cause infection in other liver cells.
This article discusses the structure of HBV, how it affects the body, and how to manage and prevent hepatitis B.
The HBV is a small DNA virus with a complex structure. It has an outer shell and an inner core, which contains the genetic material responsible for the infection. It spreads through bodily fluids, such as semen and blood. For example, someone might contract the virus by sharing a needle with someone with HBV.
HBV causes hepatitis B, which is a serious disease that can lead to liver damage and death. The disease can be acute or chronic. Chronic cases are more likely to occur following infection in infancy and early childhood, while less than
HBV is a common infection worldwide. According to the
The life cycle of HBV is a multistep process and occurs as follows:
- Entering the liver cell: The virus first attaches to the liver cell and enters it. This is the beginning of the infection. The virus moves to the nucleus of the liver cell, which is where DNA processes occur in a cell.
- Formation of covalently closed circular DNA (cccDNA): Once inside the liver cell nucleus, the virus’s genetic material forms a unique structure known as cccDNA. This structure allows the virus to replicate itself within the cell.
- Making new virus particles: The virus uses the cccDNA to replicate itself, and the new cells leave the host cell to spread the infection elsewhere in the liver. The cccDNA stays within the host cell to integrate into the host cell DNA and continue replicating.
In some cases, after exposure to HBV, a person may experience immunosuppression from chemotherapy or a stem cell transplant. When this occurs, HBV can reactivate or flare. In such cases, if someone is due to have chemotherapy or will experience another situation that may cause immunosuppression, a doctor may provide prophylactic hepatitis B management to prevent reactivation or flare of the virus.
Early stage symptoms of acute hepatitis
- joint or muscle pain
- nausea and vomiting
- abdominal pain
- clay-colored bowel movements
- dark urine
- loss of appetite
In many cases, the body is able to eliminate the virus without any problems. However, if a person still has an infection after 6 months, doctors refer to it as chronic hepatitis B. Many people with chronic hepatitis B may not experience symptoms and remain free from symptoms for many years.
If symptoms appear, they are typically similar to those of an acute infection. People with a chronic hepatitis B infection are more likely to experience liver damage and may develop cirrhosis and liver cancer.
Treatments for HBV aim to stop the disease from developing and potentially damaging the liver. Currently, there is no standard treatment or medication for routine acute hepatitis B infections. Additionally, most cases of acute hepatitis B do not require aggressive medical treatment. As such, doctors may recommend rest, adequate nutrition, and fluids.
Doctors will typically treat chronic hepatitis B with options that
- Antiviral medications: These drugs can reduce the ability of the virus to multiply, slowing down liver damage. Some people may need permanent medication as these drugs do not cure the condition.
- Regular monitoring: Regular checkups, blood tests, and liver imaging help in managing the disease and preventing complications.
- Liver transplants: In severe cases, the damage is sufficient for a liver transplant.
The most effective way of preventing HBV is through
Other preventive measures include safe practices, such as wearing a condom during sex, sterilizing all needles before injections, and not sharing needles if a person injects drugs.
HBV is a common virus that causes hepatitis B. The disease can be acute or chronic and can cause serious long-term damage to the liver that may be fatal. HBV enters liver cells and creates a template to replicate itself inside the nucleus before triggering infection in new liver cells. It can damage the liver as it continues to spread.
People can receive a vaccination against HBV, which prevents the virus from causing hepatitis B. The vaccine is safe and effective. People can also avoid activities, such as sharing contaminated needles, that cause HBV to spread. Chronic hepatitis B treatment may require lifelong medication and, in severe cases, may require a liver transplant.