What is Hepatitis B?

Hepatitis B is an infection of the liver caused by a Virus known as the Hepatitis B Virus. This infection is endemic in Southeast Asia, Africa and China but has a low prevalence in the United States, South America and Western Europe. There is an intermediate risk of Hepatitis B infection in places such as Japan, Former Soviet Union (such as Russia and Ukraine etc.), India, Northern Africa, Southern and Eastern Europe and the Middle East.

W.H.O (World Health Organization) Hepatitis B Map showing the Prevalence rate across the countries of the World

Hepatitis B Transmission

1. Blood transfusion
2. Organ transplant
3. Acupuncture
4. Sharing of tooth brush or Razors
5. Needle piercing such as use of needles in the hospital or through Tattoos
6. Drug abusers though sharing of needles
7. Sexual intercourse
8. Transmission from Mother to child

Complications and Impacts of Hepatitis B worldwide

Transmission of Hepatitis B from mother to child is a growing concern worldwide and most infections occur at the time of delivery of the baby when it comes in contact with the maternal blood. Infection may still occur while the baby is in the womb and the more the age of the pregnancy, the more likely the chance of infection. Hepatitis B is highly infectious as much as 100 times more infectious than HIV and 10 times more infectious than Hepatitis C. The Virus can be spread and remains infectious outside the body for as long as 7 days. Hepatitis B cannot be spread by coughing, hugging, use of the same cups or dishes or eating food together. Infected mothers who are breastfeeding their babies cannot transmit the infection to their babies unless the nipples are cracked and bleeding, but a woman is undergoing treatment for Hepatitis B should not breastfeed at the same time. Kissing does not transmit Hepatitis B unless the saliva is contaminated with blood. An easy to remember way for getting Hepatitis B is to know that anytime your blood comes in contact with the blood of an infected individual, you could get infected.

Hepatitis B incubation period is from 6 weeks to 6 months (60 to 90 days) with average of about 2 to 3 months.

How people get infected by Hepatitis B including infants

Hepatitis B antigens (Serological markers)

Hepatitis B has different antigens that help in knowing the nature of the infection (whether it is there for long (chronic) or it was recent infection (acute)). They are serological markers that show a picture of the nature of the infection.

1. HBsAg: this is called the Hepatitis B Surface Antigen. This is used for screening and only shows if someone is infected or not, A positive surface antigen shows there is infection.
2. HBcAg: the Hepatitis B Core Antigen
3. HBeAg: this is the Hepatitis B envelope Antigen. Its presence shows there is ongoing replication

Structure and Antigens of the Hepatitis B Virus

The surface antigen shows whether there is the presence of Hepatitis B infection but does not show whether it has been in the body for long or not. A positive Hepatitis B virus Core antigen shows the infection has been in the body for a long time.

Detection of Envelop antigen shows the Hepatitis B Virus is replicating (a form of division or reproduction) and hence, it can be transmitted to another person.

The Hepatitis B Virus

What is Hepatitis B virus?

Hepatitis B virus belongs to a family of viruses known as Hepadnaviridae. Hepatitis B viruses are spherical and tubular in shapes with a double stranded DNA material. The virus can be made to be inactive when heated to a temperature of 60⁰ for 10 hours. It can also be rendered inactive by use of Hypochlorite or 2% glutaraldehyde for 10 minutes.

Hepatitis B virus infection has an incubation period of 4 to 12 weeks

Acute Hepatitis B infection with Recovery: Typical serologic course

Hepatitis B symptoms and signs

1. Yellow discoloration of the eyes known as Jaundice
2. Fever
3. Poor appetite (anorexia)
4. Malaise (feeling of being sick)
5. Fatigue (easily getting tired)
6. Pain in the upper part of the abdomen
7. Joint pains (Polyarthritis)
8. Arteritis
9. Muscle pains
10. Skin rashes
11. Dark yellow urine
12. There may be swelling of the legs (edema) and also abdominal swelling (ascites) these occur if there is liver failure
13. Glomerulonephritis manifesting with reddish discoloration of urine

Sudden yellowish eyes or Skin is one of the symptoms of Hepatitis B

Most of the people having Hepatitis B infection may not show any sign and are said to be asymptomatic and those showing symptoms must not have all the listed symptoms; in fact, it is unlikely that one person may show all the symptoms. Out of 100 adults having Hepatitis B in their adulthood, only 10 may progress to chronic liver disease but as much as 90 children may progress to liver disease.

Treatment could be by drugs, supportive or surgery (liver transplant)

Diagnosis of Hepatitis B infection

The Hepatitis B surface antigens appear in the serum about 2 to 10 weeks after infection and can be used in the diagnosis of this infection. After some weeks, antibodies are produced (IgG). The period between the disappearance of the HBsAg (surface antigens) and appearance of the Anti-HBs (antibodies) is called the Window Period. Sometimes, a liver biopsy may be taken if there is suspicion of chronic liver disease which the biopsy may show the degree of fibrosis and inflammation.

Hepatitis B treatment options and Medications

1. Lamivudine
2. Pegylated Interferon alfa -2A
3. Interferon (this and the pegylated form is given by shots)
4. Adefovir dipivoxil
5. Entecavir
6. Tenofovir
7. Entricitabine
8. Clervudine
9. Telbuvudine (often combined with Lamivudine)
10. Liver transplant can cure the disease but reinfection may occur due to the remnants of the Hepatitis B virus in the circulation

Anti-viral drugs are not given in acute Hepatitis B and treatment is given when the Hepatitis B viral load is more than 100,000 copies/ml of HBV DNA. The cost of treatment for Hepatitis B can be very expensive.

Response of the Immune system to Hepatitis B infection with time and associated changes in the Liver

Hepatitis B definition of terms

Active carrier: refers to someone who has Hepatitis B infection in which the virus is replicating and ALT is raised.

Inactive carriers: in this, the Hepatitis B virus is replicating but the level of ALT is normal or slightly increased

Chronic Hepatitis B inactive Carrier: refers to anyone who has been persistently infected with Hepatitis B Virus but has a normal ALT level (Alanine aminotransferase)

Chronic active Hepatitis B: this refers to an inflammatory disease of the liver caused by Hepatitis B virus that is more than 6 months and can lead to liver cirrhosis. The progression to liver cirrhosis is dependent on the replication of the virus and the long standing inflammatory condition of the liver. It may take years for Hepatitis B to cause liver damage (such as cirrhosis or liver cancer)

Hepatitis B complications

1. Hepatocellular carcinoma (HCC) which refers to cancer of the liver
2. Liver Cirrhosis
3. Liver failure
4. Chronic active Hepatitis

Most people infected by Hepatitis B do fully recover but some do progress to liver failure and liver cancer. It is a serious disease that can lead to death; however, there is a vaccine for its prevention.

Hepatitis B Prevention

1. Vaccination: active immunization is done by taking 3 injections: one at stat, then after 1 month and lastly after 6 months, the injection is administered on the arm. Passive immunization can be given by administering Hepatitis B Immune Globulin – HBiG (It is prepared from plasma with high amount of anti-HBs). HBiG gives immunity for a short period of time and is usually given to high risk groups. Smoking, obesity, extremes of age, immune-compromised patients (people with low immunity), chronic kidney disease (CKD) patients and patients undergoing Hemodialysis need to repeat the vaccination as their immune response may be poor.
2. Avoid sharing of needles
3. Avoid taking of alcohol because it can make Hepatitis B infection worse
4. Eat a healthy balanced diet
5. Screening of Pregnant women during Antenatal care (ANC) for Hepatitis B, if they are found to be positive, vaccination can help prevent spread of the infection to the baby

Routine screening of blood during blood donation

Hepatitis B Vaccinations Schedules and Guidelines

There are 2 types of Hepatitis B Vaccines which are: Engerix B (by GlaxoSmithKline) and Recombivax HB (by Merck). These are recombinant DNA vaccines. You will be given 3 doses of the Vaccine which will help your body develop immunity against the infection. The Hepatitis B vaccines schedule should be started as soon as possible and it is recommended for all children below the age of 18 years, adults who need protection from being infected by the virus and anyone at risk such as patients undergoing dialysis. Adults can also be given the vaccine. The 3 shots of the Hepatitis B vaccine are usually given within 6 months and will enable your body develop immunity for life. Infants or babies born to Hepatitis B infected mothers should be given the HBiG and also a shot of the vaccine within 12 hours of birth.

The side effects of the Hepatitis B Vaccines may include mild fever and sore or swelling at the injection site. Some people could also develop allergies against the vaccines but this side effect is very rare. Pregnant women can still get vaccinated but it only helps their body develop immunity, after giving birth, the baby still needs to be vaccinated. If you have been vaccinated for Hepatitis A or C, you still need to take the Hepatitis B Vaccine because all the vaccines are different and taking one does not develop immunity against the other types of Hepatitis. There are also Hepatitis B vaccines combinations with other vaccines such as Comvax (Haemophilus influenzae type b (Hib) vaccine combined with Hep B)