Hepatitis B is a viral infection that affects the liver. It can either be acute (short-term) or chronic (lifelong) in duration. Those who develop chronic hepatitis B infection have an increased risk of developing liver cancer.

It is caused by the hepatitis B virus (HBV), which is spread through bodily fluids like blood and semen. This can occur through:

• Childbirth, from mother to child;
• Blood transfusions;
• Sharing of unsterilized needles, knives, or razors;
• Sexual intercourse.

Those who have an acute infection typically show symptoms within 3 months of getting the virus, including:

• Fever
• Skin rash
• Joint and muscle pain
• Weakness
• Nausea and loss of appetite
• Yellowish skin
• Dark-colored/brownish urine
• Stomach pain

Symptoms of a chronic HBV infection may be similar to an acute infection; the main difference is that an acute infection should only last less than 6 months, while a person with a chronic infection can develop symptoms years after getting the virus. Some individuals can be infected but remain asymptomatic. Infants and young children usually show no symptoms.

A simple blood test can diagnose HBV infection. Other additional tests may be done to evaluate how much damage the liver already has.

Most acute infections resolve on their own and do not require any treatment. Supportive care, such as getting enough rest and eating healthy, is enough for most cases. 

For chronic infections, anti-viral medications for treating hepatitis B are available over the counter but will first need the assessment of a physician. Very severe cases may lead to liver failure that will require liver transplantation.

The best way to prevent hepatitis B is by getting vaccinated. The hepatitis B vaccine is typically given as a series of three shots within a period of 6 months. Infants are usually given the first dose within 24 hours after birth. The entire series is needed for long-term protection.

Other preventive measures include:

• Regular and proper handwashing.
• Consistent and correct condom use.
• Avoiding illegal street drugs, especially those that use injections.
• Use of safe and clean injecting equipment (e.g., syringes) and equipment/supplies for procedures like piercings, tattoos, and acupuncture.
• Not re-using or sharing sharp or potentially injurious items like razors, toothbrushes, and nail clippers.
• Cleaning up spilled and possibly infectious blood using a mixture of water and bleach.

It is recommended that screening for hepatitis B be done for particular population groups, including but not limited to:

• All pregnant women;
• Men who have sex with men;
• Injecting/IV drug users;
• Hemodialysis patients;
• Blood and organ donors;
• Infants of HBV-infected mothers.