Many people avoid the name hepatitis B virus at all costs, not just because it is contagious, but also because it is very difficult to cure.

In fact, with a scientific and correct understanding of hepatitis B, one will find that it is not as terrifying as imagined. Today, let's learn together what the consequences of chronic hepatitis B virus infection are.

I. Immune tolerance

After the hepatitis B virus enters liver cells, it sheds its outer shell and allows its viral DNA to enter the nucleus of the liver cell, integrating with the DNA inside the nucleus to form covalently closed circular DNA, also known as cccDNA.

cccDNA is highly stable and difficult to be cleared by the immune system, and it uses itself as a template to continuously replicate new hepatitis B virus particles, which then exit the liver cells and enter the bloodstream.

If the body does not mount an immune response to the hepatitis B virus, the results of the five hepatitis B markers test will show "positive for three major markers," and the hepatitis B virus DNA level will also be high. However, since the liver itself has not been damaged by the virus, liver function indicators such as transaminases remain normal, and infected individuals generally show no symptoms.

This state of peaceful coexistence between the human body and the virus is medically referred to as immune tolerance, commonly known as a "chronic hepatitis B virus carrier." This state can persist for a considerable period, and if it can be maintained throughout a lifetime, it generally does not cause major problems.

II. Weaker immune response

If the infected individual has a lower immunity and a weaker ability to clear the hepatitis B virus, the results of the five hepatitis B markers test may still show "positive for three major markers," and the hepatitis B virus DNA level may be high but slightly lower than in the immune tolerance state.

The body may experience symptoms such as fatigue and loss of appetite. Liver function may show mild to moderate abnormalities, such as a persistent 1–2-fold increase in alanine transaminase (ALT), which is termed subclinical hepatitis.

Because this condition is often subtle, it requires greater attention. Patients should actively undergo antiviral treatment under medical guidance. Otherwise, the body’s long-term immune response to the virus can cause ongoing damage to liver cells, leading to collagen fiber formation as part of the repair process. Once collagen fibers accumulate excessively, it may result in liver cirrhosis.

III. Stronger immune response

If the body's immune response to the hepatitis B virus is strong and liver cell damage is more severe, it may lead to acute hepatitis or an acute exacerbation of chronic hepatitis. Liver function may show moderate to severe abnormalities, with multiple indicators potentially increasing or decreasing.

For patients with acute exacerbation of chronic hepatitis, most can achieve normal liver function within 6 months with appropriate antiviral treatment.

For acute hepatitis B virus infections, more than 95% of adults can self-heal within 6 months, while a small proportion may develop into chronic hepatitis, indicating that the hepatitis B virus has not been completely cleared. The remaining hepatitis B virus can lead to recurrent episodes of hepatitis and induce liver cirrhosis.

IV. Strong Immune Response

If the majority of liver cells are infected with the hepatitis B virus and the immune system is robust, a strong immune response may occur. This can lead to extensive damage and necrosis of liver cells, potentially resulting in severe hepatitis (liver failure) and even life-threatening crises.

However, severe hepatitis is relatively rare in patients with acute hepatitis B. Moreover, if patients safely pass the critical period, the prognosis is generally favorable, and most of the hepatitis B virus can be cleared.

The above outlines the four potential consequences of chronic hepatitis B virus infection. We hope this information helps in understanding hepatitis B better.