Hepatitis B - the most important thing you need to know about the disease

Key Facts

Hepatitis B is a viral infectious disease that affects the liver and occurs in acute or chronic form.
Transmission of the virus most often occurs perinatally from mother to child, as well as through contact with blood or other biological fluids, in particular during sexual contact with an infected partner, unsafe injection practices, cuts with piercing instruments in medical practice and in domestic conditions, and also among people who inject drugs.
WHO estimates that in 2021, there were 296 million people worldwide living with chronic hepatitis B (i.e. positive for hepatitis B surface antigen).
An estimated 820,000 people died from hepatitis B in 2021, primarily as a result of hepatitis-related liver cirrhosis and hepatocellular carcinoma (primary liver cancer).
As of 2021, 30.4 million (10)% of all people living with hepatitis B were aware of their infection, and 6.6 million (22%) of all diagnosed patients were receiving treatment. According to the latest WHO estimates, in 2021 the proportion of children under five years of age with chronic hepatitis B has fallen to just under 1%, compared with the decades before the introduction of vaccination (i.e. from the 1980s to the early 2000s). x years) this figure was about 5%.
According to WHO estimates, in 2021, despite the availability of a highly effective vaccine, the number of people primarily infected with hepatitis B was about 1.5 million people.
Hepatitis B is preventable through safe, accessible and effective vaccines.

Hepatitis B is a potentially life-threatening infectious liver disease caused by the hepatitis B virus (HBV). This disease is a major health problem worldwide. The infection can become chronic with a high risk of death from cirrhosis and liver cancer.

There is a safe and effective vaccine that provides 98–100% protection against hepatitis B. Prevention of viral hepatitis B helps prevent the development of complications such as chronic hepatitis and liver cancer.

Hepatitis B: carriage or disease leading to cirrhosis and cancer?

Hepatology, the study and development of new treatments for liver disease, has made incredible progress over the past two decades. Methods for accurate virological assessment of the activity of hepatitis C and B viruses in the human body, which are the most common causes of chronic hepatitis, cirrhosis, and liver cancer, have been developed and implemented. So-called “non-invasive” methods have been developed and are widely used, that is, without the use of liver biopsy, diagnosing the degree of liver damage, or establishing the stage of cirrhosis. Even more impressive progress has been made in the treatment of these diseases. We have discussed the problem of hepatitis C many times. One has only to add that a new era is opening in the treatment of hepatitis C - drugs with a direct antiviral effect have been developed and are already beginning to be used, thanks to which it is believed that within a decade it will be possible to achieve one hundred percent effectiveness of treatment. In this article we will talk about hepatitis B and new advances in its treatment.

Symptoms of hepatitis B disease

The main signs of pathology include the following:

nausea and appetite disturbances;
increased weakness and fatigue;
yellow tint of the skin;
painful sensations in the area of the right hypochondrium;
dark shade of urine.

There is also a fulminant form of development of the disease, in which swelling of the brain develops within a few hours, and the patient falls into a coma. Treatment in this case turns out to be ineffective, and the patient’s death occurs within a short period. Most often, hepatitis occurs in the acute stage, when pronounced symptoms of intoxication appear, followed by icteric syndrome. At the final stage, the patient recovers.

The hepatitis B virus is 100 times more contagious than HIV (human immunodeficiency virus).

Despite the widespread introduction of vaccination against hepatitis B, the prevalence of the disease remains high. In different regions of Russia, the prevalence of carriage of the virus ranges from 1.5% to 11.5%. As with hepatitis C, the source of infection is the blood of an infected person. The routes of infection are similar: the use of non-sterile needles, instruments for various medical and non-medical (piercing, tattoos, manicure/pedicure) manipulations, the use of personal hygiene items of an infected person in everyday life (razor, scissors, toothbrush, etc.), unprotected sexual contact, transmission of the virus from an infected mother to her child. The hepatitis B virus is more stable in the external environment and more contagious than the hepatitis C viruses and human immunodeficiency viruses. Therefore, the natural routes of transmission of the B virus (sexual transmission and mother-to-child transmission) are more significant for this virus.

Effectiveness of vaccination

As of 2013, 183 Member States were vaccinating infants against hepatitis B as part of their national vaccination schedules, and 81% of children had received hepatitis B vaccination. This represents significant progress compared to 31 countries in 1992, when the World Assembly Health Council adopted a resolution recommending global vaccination against hepatitis B.

Additionally, as of 2013, 93 Member States have introduced hepatitis B dose provision at birth. Since 1982, more than one billion vaccine doses have been used worldwide.

In many countries where typically 8% to 15% of children had chronic hepatitis B virus infection, vaccination has reduced rates of chronic infection among immunized children to less than 1%.

How to protect yourself from hepatitis B?

The only means of protection is vaccination against hepatitis B, which is currently administered to all newborn children and adolescents. Adults with risk factors for infection should also be vaccinated. The hepatitis B vaccine is one of the safest vaccines in the world. Three-time administration of the vaccine according to a special scheme leads to the formation of specific antibodies that prevent the development of hepatitis B disease in 98% of those vaccinated. Immunity lasts for at least 8-10 years, but often remains for life.

Prevention

The main method of preventing hepatitis B is vaccination. WHO recommends that all newborns be vaccinated against hepatitis B as soon as possible after birth, within the first 24 hours of life if possible, followed by two or three doses of the vaccine at least four weeks apart to ensure full vaccination. Timely vaccination of children immediately after birth is an effective way to reduce the incidence of mother-to-child transmission of hepatitis B.

According to the latest WHO estimates, worldwide in 2021 the proportion of children under five years of age with chronic hepatitis B has fallen to just under 1%, compared with the decades before the introduction of vaccination (i.e. from the 1980s to early 2000s) this figure was about 5%.

This has achieved one of the Sustainable Development Goal targets for viral hepatitis elimination: reducing the prevalence of HBV infection among children under five years of age to less than 1% by 2021. This success was achieved in a number of regions with the exception of sub-Saharan Africa.

Increasing hepatitis B vaccination coverage worldwide over the past two decades has been a major public health achievement and has contributed to a decline in the incidence of hepatitis B infection among children.

In 2021, three-dose vaccine coverage reached 85% worldwide, up from around 30% in 2000. However, rates of newborn immunization against hepatitis B remain variable. Thus, the average rate of vaccination coverage with the first dose of hepatitis B vaccine immediately after birth is 43% worldwide, but in the WHO African Region it is only 6%.

A full course of vaccination produces protective antibodies in more than 95% of infants, children and young adults. Immunity acquired through vaccination lasts for at least 20 years and probably throughout life. Therefore, WHO does not recommend booster vaccinations for people who have completed the three-dose vaccine.

In countries with low or moderate endemicity of hepatitis B, vaccination is indicated for all unvaccinated children and adolescents under 18 years of age. In these countries, high-risk groups are more likely to become infected and should also be vaccinated. These risk groups include:

individuals who frequently require blood or blood products, dialysis patients, and solid organ transplant recipients;
prisoners in places of deprivation of liberty;
injection drug users;
persons who have household and sexual contact with people with chronic HBV infection;
persons with multiple sexual partners;
healthcare workers and other persons who may have contact with blood and blood products while on duty;
International travelers who have not completed a full course of HBV vaccination and who are eligible for vaccination before departure to HBV-endemic areas.

The vaccine has an excellent safety and efficacy record and has reduced the proportion of children under five years of age with chronic HBV infection to just under 1% in 2021, compared with the decades before the introduction of the vaccine (i.e. since the 1980s). until the early 2000s), this figure was about 5%.

In addition to infant vaccination, which includes a timely first dose immediately after birth, WHO recommends prophylactic antiviral therapy to prevent mother-to-child transmission of hepatitis B. Pregnant women with a high concentration of HBV DNA (high viral load) and/or the presence of HBeAG in the blood are at high risk of transmitting the virus to their unborn child, even if the child receives the first dose of vaccine immediately after birth and completes the full course of vaccination against hepatitis B. Therefore, pregnant women with high The concentration of HBV DNA during pregnancy may indicate a prophylactic course of antiviral therapy to prevent perinatal HBV infection and protect the unborn newborn from the disease.

In addition to infant vaccination and prevention of mother-to-child transmission, HBV transmission can be prevented through blood safety measures, including quality screening of all donated blood and blood products used for transfusion. Globally, 97% of donated blood units were screened and quality controlled in 2013, but gaps remain. Effective measures to prevent the transmission of hepatitis B virus include ensuring safe injections and avoiding unnecessary injections and injections performed in unsafe conditions. Between 2000 and 2010, the rate of unsafe injections worldwide fell from 39% to 5%. In addition, one of the effective measures to prevent infection is to improve the safety of sexual intercourse, including minimizing the number of sexual partners and the use of barrier contraception (condoms).

Hidden disease

As with hepatitis C, the acute phase of the infection often occurs without jaundice. In the vast majority of cases, patients with acute hepatitis B recover and acquire lifelong immunity to re-infection (protective antibodies to viral proteins are detected in their blood serum). After infection, some people become carriers of the HBsAg virus protein, also called the “Australian antigen.” Carriage most often occurs when infected in childhood. In a small proportion of patients, acute hepatitis drags on and becomes chronic. Chronic hepatitis B, like chronic hepatitis C, often occurs latently and unnoticed for a long time. For many years, a person can feel absolutely healthy, and the first symptoms of the disease appear only at the late stage of liver cirrhosis, when the disease is more difficult to treat and the overall prognosis is unfavorable.

What is important to know about the forms of hepatitis B virus infection?

Chronic infection can occur in two main forms:

The first form is inactive carriage of HBsAg. It is characterized by the absence of viral particles in the blood serum or their detection in a low titer, the absence of inflammation in the liver and, as a rule, a non-progressive course. With a decrease in immunity, inactive carriage of HBsAg can turn into the active form of hepatitis B.

The second form is chronic active hepatitis B. It is characterized by the presence of a large number of viral particles in the blood, the presence of inflammation in the liver, which is reflected in changes in the so-called liver tests (or enzymes), and a progressive course with the risk of developing cirrhosis and liver cancer. In recent years, it has been found that the higher the concentration of virus in the blood, or “viral load,” the higher the risk of developing cirrhosis and liver cancer.

It is impossible to distinguish between these two forms based on the patient’s well-being and only clinical signs of the disease (which, as with inactive carriage, may be completely absent in a patient with chronic hepatitis B).

Hepatitis D

The infection is caused by the hepatitis D virus (HDV virus).
Quite a specific disease.

It cannot exist independently, and, as a rule, comes in combination with the hepatitis B virus (HBV).

The hepatitis D virus is transmitted during sexual intercourse or through the exchange of needles among intravenous drug users.

Relatively common transmission from an ill pregnant woman to the fetus.

It is possible to become infected through blood transfusions or dialysis, but this is very rare in developed countries.

What to do if you are diagnosed with HBsAg?

Unfortunately, hepatologists are often faced with underestimation on the part of the patient, as well as doctors of other specialties, of the seriousness of HBsAg detected over many years. A patient who is diagnosed with HBsAg for the first time must undergo an examination, which will make it possible to make a correct diagnosis - to distinguish between inactive carriage of HBsAg and active chronic hepatitis B that requires treatment. To do this, the hepatologist will suggest that you do a number of studies: - a study of a biochemical blood test, - a study of the viral load using quantitative PCR (polymerase chain reaction) - a study for the presence of another protein (or antigen) of the hepatitis B virus, which characterizes the high infectiousness of the patient, — HBeAg — study for the presence of a companion virus of hepatitis B - delta virus — study of alpha-fetoprotein (tumor marker of a liver tumor) — ultrasound examination of the liver — fibroelastography to clarify the stage of liver fibrosis (other studies are possible according to indications)

Modern treatment of chronic hepatitis B can stop the disease!

If you are nevertheless diagnosed with chronic hepatitis B, it is necessary to prescribe antiviral treatment, that is, treatment using drugs that can block the replication of the virus.

The goal of modern antiviral therapy for chronic hepatitis B is to persistently suppress the replication of the virus, achieve remission of the disease, that is, transfer the process to an inactive state. When this result is achieved, the development of liver cirrhosis and its complications (such as ascites, internal bleeding, liver failure) is prevented, and the risk of developing liver cancer is greatly reduced.

A number of drugs with antiviral effects are currently registered for the treatment of chronic hepatitis B. Among the new generation of drugs there are safe drugs that can be used for several years, drugs to which the virus does not develop resistance. Your attending physician will help you choose a treatment appropriate to the stage and form of your disease.

Treatment

Medical care for hepatitis B is aimed at maintaining comfort and a rational combination of nutrients, including replacing fluid lost as a result of vomiting and diarrhea. People with chronic hepatitis B who need treatment can be treated with medications, including oral antivirals (such as tenofovir and entecavir) and interferon injections. Treatment of hepatitis B may slow the progression of cirrhosis, reduce the incidence of hepatocellular carcinoma, and improve long-term survival. However, in many resource-poor areas, access to such treatment is difficult.

Liver cancer is almost always fatal and often occurs in people who are in their prime productive years and are providing for their families. In developing countries, most people with liver cancer die within months of diagnosis. In high-income countries, surgery and chemotherapy can prolong life by several years. Patients with cirrhosis sometimes undergo liver transplants, with varying degrees of success.

Is it necessary to follow a diet for patients with chronic hepatitis B?

No special diet is required for chronic viral hepatitis, however, you should avoid drinking alcohol even in small doses, since the combined effect of alcohol and the virus on the liver significantly increases the risk of developing cirrhosis and liver cancer. If you are overweight, you should limit your intake of fats and high-calorie foods, since fat deposition in the liver accelerates the development of cirrhosis. Factors that reduce immunity, in particular sun exposure, should be avoided, that is, you should not use a solarium or sunbathe on the beach. It is advisable to quit smoking. You can continue to exercise. Swimming and hardening procedures that support the state of your immunity are useful.