What should you know about what causes hepatitis B and AIDS?

Hepatitis B and HIV are separate viral infections. Hepatitis B mainly targets the liver. HIV affects the immune system; AIDS is a term for advanced HIV-related immune damage, not the name of the virus itself. Having hepatitis B does not mean a person has HIV or AIDS, and an HIV diagnosis does not by itself prove hepatitis B infection.

The infections can share transmission routes, including sexual contact and exposure to infected blood, which is why clinicians may discuss testing for more than one infection after a risk event. Symptoms such as fatigue or dark urine do not identify which virus is present. Learn about [Hepatitis B](/conditions/hepatitis-b/) separately.

Seek confidential medical advice for testing after sexual contact, shared needles, an unsterile procedure, or another blood exposure. Tell the clinician when the exposure happened and what protection was used; timing can affect which tests and preventive steps are considered.

Ask about [Hepatitis B Vaccination](/treatments/preventive-care-and-vaccination/hepatitis-b-vaccination/) if you are not protected. If hepatitis B is suspected or confirmed, a [Liver Function Test](/treatments/diagnostics-and-screening/liver-function-test/) may help assess the liver, but it cannot diagnose HIV.

Contact a clinic promptly after a recent exposure so appropriate testing and prevention can be discussed. Seek urgent help for confusion, severe vomiting, yellowing of the eyes with worsening illness, unusual bleeding, or severe abdominal swelling. Dark urine or fatigue should be assessed in context; see [Dark Urine](/symptoms/dark-urine/) and [Fatigue](/symptoms/fatigue/).

Ask which tests are appropriate, whether you need hepatitis B vaccination, whether HIV prevention or testing is relevant, and when results should be reviewed.