Last Updated on June 4, 2020 by Shuvani Sanyal, MD
Hepatitis B (hep B) is an infectious liver disease caused by the hep B virus (HBV). Effective vaccines can prevent HBV. The majority of reported acute HBV infections in the United States are among adolescents and young adults. Sexual contact is the most common means of transmission.
Hepatitis B Prevalence
Approximately 350 to 400 million people have been infected with hep B worldwide. Hep B infections cause upwards of 620,000 deaths worldwide each year. There are an estimated 1.25-2.0 million chronically infected Americans, of whom 20% to 30% acquired their infection during childhood.
More than 95% of adults recover spontaneously within 6 months; however, 90% of young children who get infected with HBV never clear the virus, remaining chronically infected with an increased risk of scarring of the liver (cirrhosis) and liver cancer.
An estimated 38,000 new cases occur each year and about 3,000-5,000 deaths annually are related to HBV infections and resultant cirrhosis and liver cancer.
Hepatitis B Transmission
Transmission of HBV can occur when blood or bodily fluids from an infected person enter the body of a person who is not immune, similar to HIV, the virus that causes AIDS. However, HBV is 100 times more infectious than HIV.
The highest concentrations of HBV are found in blood, semen, and vaginal secretions. HBV is not spread through food or water, sharing eating utensils, breastfeeding, hugging, kissing, coughing, sneezing, or by casual contact. The virus is infrequently transmitted by blood transfusions, because blood for transfusion is tested for HBV contamination.
Examples of possible transmission modes include:
- Sexual contact including foreplay with an infected person without using a barrier;
- Sharing drugs, needles, syringes, water, or ‘works’ when shooting drugs;
- Getting an injury through needle sticks or sharps that may be contaminated;
- Infected mother to her baby during birth;
- Tattooing, body piercing, and acupuncture by virus-contaminated instruments;
- Sharing of toothbrushes, razors or other personal care items that may have blood on them.
The following groups are especially at risk:
- Persons with multiple sex partners or with a diagnosis of a sexually transmitted disease;
- Men who have sex with men;
- Sexual contacts of infected persons;
- Injection drug users;
- Household contacts of chronically infected persons;
- Infants born to infected mothers;
- Infants and children of immigrants from areas with high rates of HBV infection;
- Health care and public safety workers;
- Hemodialysis patients;
- Adults between 20-49 years of age (highest rate of infection).
Hepatitis B Symptoms
During early infection, about 70% of adults will have no symptoms or few symptoms.
Significant symptoms develop in the remaining 30% of acute cases of hep B several months later which can include jaundice (yellowing of the skin and eyes), light colored stools, and dark urine.
Other possible symptoms can include fatigue, abdominal pain, loss of appetite, nausea, vomiting and joint pain.
Hepatitis B Diagnosis
The only way to know if you are currently infected with HBV, have had the infection and have recovered, or if you are chronically infected, is to get tested for hep B. Different serologic ‘markers’ or combinations of markers are used to identify different phases of HBV infection and to determine whether a patient has acute or chronic HBV infection, is immune to HBV as a result of a prior infection or vaccination, or is susceptible to infection.
Testing might include –
HBsAG (hepatitis B surface antigen): When this test is positive, it means you are currently infected with HBV and are able to pass the infection on to others.
Anti-HBc (antibody to hep B core antigen): When this is positive or reactive, it means that you have HBV infection or had it at some time in the past.
HBsAb or anti-HBs (hepatitis B surface antibody): The ‘surface antibody’ is formed in response to the hep B virus. Your body can make this antibody if you have been vaccinated, or if you have recovered from a hepatitis B infection. If this test is positive, then your immune system has successfully developed a protective antibody against the hepatitis B virus.
Understanding your HBV test results can be confusing. It is important to discuss your test results with your health care provider so that you can clearly understand whether you have a new infection, chronic infection, or have recovered from an infection.
– – – –
Have you recently been exposed to hepatitis b or think you might have a hep B infection? Did you learn something new because of this post? Share your thoughts in the comments section below!