What should you know about hepatitis B transmission?

Hepatitis B spreads through infected blood and certain body fluids, including during sex, childbirth, or shared needles. It can also spread through unsterile equipment used for injections, tattoos, piercings, or medical procedures. The virus does not spread through ordinary social contact such as hugging, sharing meals, or sitting nearby.

A person can carry hepatitis B without feeling ill and may pass it on without knowing. Risk depends on whether infected fluid reached broken skin, a mucous membrane, or the bloodstream. Sharing razors or toothbrushes can create a blood exposure, even when blood is not visible. Kissing and saliva alone are not usual routes of transmission, but blood in the mouth can change the situation. Hepatitis B can cause fatigue or dark urine, although symptoms are not required.

Hepatitis B vaccination is a key preventive measure. Use sterile equipment, do not share needles or personal items that may carry blood, and use barrier protection during sex until a clinician confirms that protection and testing are adequate. If someone in your household or sexual partnership has hepatitis B, ask about testing and vaccination. A clinician may arrange a Liver Function Test or other blood tests when infection is possible. Do not donate blood while a possible infection is being assessed.

Contact a healthcare professional promptly after needlestick injury, unprotected sex with a person who may have hepatitis B, or contact between infected blood and broken skin or eyes. Preventive treatment may be time-sensitive. Seek urgent care for yellow eyes or skin, severe vomiting, confusion, or rapidly worsening illness.

Ask what type of exposure occurred, whether you need hepatitis B testing or vaccination, and whether anyone close to you should be tested. Ask how long to use extra precautions and which symptoms should prompt review.