Hepatitis B is a common, serious liver infection in which a virus called hepatitis B virus (HBV) attacks the hepatocytes and causes inflammation of liver tissue. The virus is transmitted by contact with infected blood and other body fluids. In half of the cases, no signs and symptoms will appear. The others may experience some complains, such as jaundice, nausea, and general feeling of weakness and sickness.

The disease may last fewer than 6 months to be called acute hepatitis B. if the patient didn’t cure from hepatitis B after this period, he will be recognized as having chronic infection. The risk of developing chronic hepatitis B increases significantly if the first infection with HBV accrued in smaller age.

Blood tests for hepatitis B virus markers will show if the person is affected or not, and weather hepatitis B is acute or chronic. Based on the results, the doctor will determine the best action. Chronic hepatitis B requires more attention; as it can develop to more drastic health conditions, like liver cirrhosis and cancer, which cause most of deaths by hepatitis B disease.

There is no specific treatment for acute hepatitis B. however, supportive treatment may be indicated for some people with severe clinical manifestations. Chronic Hepatitis B infection can be treated with drugs, including oral antiviral agents and interferon. Treatment can slow the progression of cirrhosis, reduce incidence of liver cancer and improve long term survival. Liver transplantation is the last something can be done to these patients.

Prevention of hepatitis B is much possible; as a very effective and safe vaccine is available. All new babies and people under the risk of hepatitis B disease – such as health workers, travelers to affected areas, and those need frequent blood transfusion – should take HBV vaccine doses. Illicit drugs and anomalous sexual relationships - such as prostitution and anal sex - should be avoided; as they magnitude the risk of hepatitis B virus transmission.

Hepatitis B is a liver infection caused by the hepatitis B virus that spreads through blood and other body fluids. Hepatitis B is a major global health problem. It can cause chronic infection and puts people at high risk of suffering death from cirrhosis and liver cancer.

• Acute hepatitis B: an infection of the liver that happens after exposure to hepatitis B virus that passes within 6 months (usually within 1-3 months). Many infected adults won't experience any symptoms and will fight off the infection without realizing it. Others may have them, such as jaundice, nausea, and fatigue.
• Chronic hepatitis B: If the infection extends for half year or more, then it is considered a chronic disease that can later develop into liver cirrhosis or cancer. Children who are infected before the age of 6 are the most likely to develop chronic infection, especially those diseased in the first year of life.

Hepatitis B disease is caused by an infection through a virus called hepatitis B virus (HBV), which can spread through:

• Sharing needles and other drug equipment, such as spoons and filters;
• having unprotected sex with an infected person;
• Receiving a blood transfusion with the virus in a country where blood isn't tested for hepatitis B;
• sharing toothbrushes, razors, and tattooing objects contaminated with infected blood;
• Accidental needle sticks - especially at heath care settings - that had used with infected person;
• Percutaneous or mucosal exposure to saliva, menstrual, vaginal, and seminal infected fluids;
• Direct exposure to cerebrospinal, amniotic, pleural, synovial, peritoneal and pericardial fluids of affected person.
• From infected mother to her baby, particularly in countries where the infection is common.

Although these ways are the same as the human immunodeficiency virus (HIV) transmits, HBV is 50 to 100 times more infectious than HIV. However, Hepatitis B isn't spread by cheek kissing, holding hands, hugging, coughing, sneezing, breastfeeding, or sharing crockery and public pools.

Some people are more prone to be infected with hepatitis B virus, compared to others. They include:

• Unsafe sex participants. Hepatitis B virus is carried by sexual fluids. Some sexually active people are at greater risk to have hepatitis B. They are: Homosexual Men (gays), heterosexual persons with multiple sex partners, sex workers and their clients, and living with an infected partner.
• Health workers. Hepatitis B is an important occupational hazard for employees in health care settings, since they may deal with infected patients and exposed to their fluids through various means during care and crevice provision.
• Babies for infected women. The child may uptake the infection during delivery. If that happened, he/she is more likely to become carrier of hepatitis B for life, as his/her immune system is not able to fight and clear the virus from the body.
• Travelers to regions with high infection rates of HBV, such as sub-Saharan Africa, Central and Southeast Asia, and Eastern Europe. The disease is also common in the Middle East and the Indian subcontinent.
• Injecting drug user. Illicit drug addicts don’t usually adhere to safety precautions and may inject themselves with used needles that could carry the virus from infected person.
• Immunocompromised patients. The immune system acts as a defender against disease causative agents. If the immune function is weak or reduced, the person will have a greater chance to have Hepatitis B infection, particularly those who have HIV, hepatitis C virus, and people who are treated with chemotherapy or other immunosuppressive drugs.
• People who frequently require blood or blood products, dialysis patients, recipients of solid organ transplantations; as they are more susceptible to have hepatitis B if no enough infection control have been taken.

The liver is the largest organ inside the body. It helps digest food, store energy, and remove poisons. Hepatitis is an inflammation of the liver. This condition is caused by several agents, from these is hepatitis B virus that exist in the blood and other body fluids of infected person. This virus can survive outside the body for 7 days at 44 degrees and 6 months at room temperature. During this time, the virus can still cause infection if it enters the body of a person who is not protected by the vaccine. The incubation period of the hepatitis B virus is 75 days on average, but can vary from 30 to 180 days.

The pathogenesis and clinical manifestations of hepatitis B infection are due to the interaction of the virus and the host immunity. The immune system attacks HBV and causes liver injury, the result of an immunologic reaction when activated CD4+ and CD8+ lymphocytes recognize various HBV-derived peptides on the surface of the hepatocytes. Impaired immune reactions, or a relatively tolerant immune status result in chronic hepatitis. In particular, a restricted T-cell–mediated lymphocytic response occurs against the HBV-infected hepatocytes.

Most people do not experience any symptoms during the acute infection phase. However, some people may develop them usually two or three months after exposure to hepatitis B virus. Symptoms may last several weeks and include:

• fatigue;
• general aches;
• fever;
• Malaise;
• loss of appetite;
• nausea and vomiting;
• diarrhea;
• abdominal pain;
• yellowing of the skin and eyes (jaundice);
• skin itching;
• Dark urine and pale, grey-colored stool.

For some patients, the virus may cause chronic liver infection. The symptoms of chronic hepatitis B are the same as acute infection, but they tend to be quite mild and may come and go. Some people may not have any noticeable symptoms.

Symptoms are not enough to confirm hepatitis B, as they resemble with other conditions and the disease may not trigger symptoms at all. A number of diagnostic approaches, mainly blood sampling, are available to diagnose and monitor people with hepatitis B. They include:

• Blood serum tests. These tests can determine if hepatitis B virus is present and whether the disease is acute or chronic. It can also be used to monitor vaccine-induced immunity. The diagnosis of hepatitis B virus infection requires the evaluation of the patient's blood for series of serological markers of HBV that are: hepatitis B surface antigen, hepatitis B surface antibody, and hepatitis B core antibody.
• Liver function test. This common test may be used to investigate how well the liver is working. It includes measuring of many biological markers that reflect in all the health status of liver organ. The test includes measuring Albumin, Alpha-1 antitrypsin, Alkaline phosphatase (ALP), Alanine transaminase (ALT), Aspartate aminotransferase (AST), and Gamma-glutamyl transpeptidase (GGT).
• Liver biopsy. The doctor might also want to determine whether the infected person has liver damage. During this test, the doctor inserts a thin needle through the skin and into the liver and removes a tissue sample for laboratory analysis. The result can help providing information about disease progression and assessing the degree of liver damage.

• Emergent hepatitis B: Even the person has exposed to hepatitis B virus, there is a chance to prevent the disease from developing if the person received the recommended treatment as soon as possible. In these cases, the doctor may give:
  • a dose of the hepatitis B vaccine – a need also for two further doses over the next few months to give long-term protection;
  • Hepatitis B immunoglobulin – a preparation of antibodies that work against the HBV and can offer immediate but short-term protection until the vaccine starts to take effect.

These are most effective if given within 48 hours after possible exposure, but the person can still have them up to a week after.

• Acute hepatitis B: There is no specific treatment for acute hepatitis B, but if the patient has developed the symptoms, he may benefit from supportive care until bypassing the situation. This may include:
  • Getting plenty of rest and adequate nutrition and fluids;
  • Taking painkillers, such as paracetamol or ibuprofen, for pain;
  • Maintaining a cool, well-ventilated environment, wear loose clothing, and avoid hot baths or showers if itching is a problem;
  • Avoiding greasy and spicy foods, in order to prevent worsening of gastrointestinal problems.

Patients are advised to have regular blood tests after 2-3 months to check that they are free of the virus and haven't developed chronic hepatitis B.

• Chronic hepatitis B: Several treatments are available for chronic hepatitis. Even they do not provide a cure, but they offer control of the virus and a protection to the liver.  Treatment program will be set after a decision between the patient and the doctor.
  • Antiviral medications. World health organization recommends the use of oral treatments - tenofovir or entecavir, because these are the most potent drugs to suppress hepatitis B virus. They rarely lead to drug resistance as compared with other drugs, are simple to take (1 pill a day), and have few side effects so require only limited monitoring. Other medications that approved by some health agencies around the world are adefovir and telbivudine.
  • Interferon alfa-2b. Considered the first treatment offered if the liver is working fairly well and the patient has the ability to cover their high cost. This drug is a synthetic version of a substance produced by the body to fight infection by stimulating the immune system to attack the hepatitis B virus and regain control over it. It's usually given by injection once a week for 48 weeks. Side effects may include flu-like symptoms, depression, and difficulty in breathing.
  • Liver transplant. Liver transplantation is the treatment of choice for patients with liver failure secondary to chronic hepatitis B. During a liver transplant, the surgeon removes the damaged liver and replaces it with a healthy one from an appropriate donor. After the procedure, the patient may have to take some antiviral medications and vaccination to reduce the common chance of disease recurrence, which could limit the outcomes.
  • Healthy life style. Although hepatitis B cannot be controlled by healthy eating and exercise alone, following liver healthy habits may help to reduce liver damage that may progressed by the disease. Patients are advised to consult their doctors and nutritionists to set a diet plan that provide healthy and adequate foods. Limiting alcohol intake and stopping smoking may also enhance liver protection.

• Liver cirrhosis. The inflammation associated with a hepatitis B infection can lead to extensive liver scarring, which may impair the liver's ability to function. Liver cirrhosis affects around one in five people with chronic hepatitis B, often many years after they first got the infection.
• Liver cancer. According to hepatitis B foundation, chronic infection with hepatitis (B and C) causes nearly 80% of all primary liver cancers Worldwide. The risk of death from primary liver cancer is considered very high, with a 5-year survival rate of only 10%. People with chronic hepatitis B infection have significant risk of liver cancer if they developed liver cirrhosis.
• Liver failure. Acute liver failure is a condition in which the vital functions of the liver shut down. When that occurs, a liver transplant is necessary to sustain life. This may develop in few cases of acute hepatitis B that lead to a serious problem called fulminant hepatitis B, in which the immune system attacks the liver and causes extensive damage to it.

• Hepatitis B virus vaccine

World health organization (WHO) says that the available vaccine for hepatitis B virus is 95% effective in preventing infection and the development of chronic disease and liver cancer due to hepatitis B. Protection lasts at least 20 years and is probably lifelong. hepatitis B virus (HBV) vaccine named by FDA as “the first cancer vaccine” because it can prevent the major carcinogen that lead to develop hepatocellular carcinoma.

Three or four doses are given to complete the immune for prevention. The second dose should be given at least 1 month after the first dose; the third dose should be given after 2 months or more from the second dose and 4 months or more after the first dose. Early vaccination after exposure to HBV also can stop from becoming infected. WHO recommends that all infants receive their first hepatitis B vaccine as soon as possible after birth, preferably within 24 hours. People in high-risk groups mentioned in “Risk factors” should also be vaccinated.

• Safety precautions
  • Implementing of blood safety strategies, including quality-assured screening of all donated blood and blood components used for transfusion to avoid accidental transmission;
  • Applying Safe injection practices, such as eliminating unnecessary and unsafe injections and using aseptic technique to avoid contamination of sterile injection and operation equipment;
  • Regarding to safer sex practices that include minimizing the number of partners and using barrier protective measures (suitable, effective condoms);
  • Stop using illicit drugs, which can be achieved by leaving bad friends and seeking help from specialized authorities that provide support and protection for the addicted until remission;
  • Carefulness about equipment sterilization with some habitual features such as piercing, tattooing, and bloodletting.

Many people who become infected with hepatitis B never feel sick and recover completely. Others get a brief, acute illness with fatigue and loss of appetite and jaundice. Acute hepatitis B may develop to a chronic disease that could lead to serious complications with time. This depends on the age at which the person first gets the infection. As many as 90% of infants who acquire HBV infection from their mothers at birth or in infancy become chronically infected. Of children who become infected with HBV between 1 year and 5 years of age, 30% to 50% become chronically infected. By adulthood, the risk of acquiring chronic HBV infection is approximately 5%, according to Centrals for disease prevention and control, USA.

More than 686,000 people die every year due to complications of hepatitis B, as per world health organization. Although most people with chronic hepatitis B have inactive disease and will remain healthy, about one in four will have active disease that may lead to cirrhosis, liver failure, and liver cancer. According to university of Maryland medical center, Cirrhosis occurs in 5 to 10% of people with chronic hepatitis B and About 14% of people with cirrhosis develop liver cancer. The poor outcomes from chronic hepatitis B are because often no symptoms appear until the liver is severely damaged; thus early detection and adhering to recommended treatment is crucial to help dealing with the disease and continue life nearly as normal.

An estimated 240 million people have chronic hepatitis B virus infection globally. Hepatitis B prevalence is highest in sub-Saharan Africa and East Asia, where between 5–10% of the adult population is chronically infected. High rates of chronic infections are also found in the Amazon and the southern parts of eastern and central Europe. In the Middle East and the Indian subcontinent, an estimated 2–5% of the general population is chronically infected. Less than 1% of the population of Western Europe and North America is having a chronic disease.

Approximately 45% of the global population live in areas with a high prevalence of chronic HBV infection, 43% in areas with a moderate prevalence, and 12% in areas with a low prevalence. The risk for HBV infection may be higher in countries where the prevalence of chronic HBV infection is high or intermediate; expatriates and long-term development workers may be at increased risk for HBV infection in such countries.

A study at Ziauddin University, Pakistan, revealed gender differences in the prevalence of Hepatitis B. From 472 patients with HBV infection selected for the study, 79.5% were males. Male dominance was found to be consistent in all categories; acute, chronic, and that lead to cirrhosis or liver cancer. Another study at National Taiwan University showed that Androgen and estrogen pathways were identified to play opposite role in the pathogeneses and progression of hepatitis B disease, in favor of estrogen that is thought to act as a protective from the disease and defensive of hepatic cells damage and carcinogenesis.