What should you know about hepatitis A vaccine immunity?

Protection develops after vaccination rather than immediately. The timing and strength of protection can depend on your age, health, previous doses and whether you were exposed before vaccination. A healthcare professional can review your record and advise whether further vaccination or testing is appropriate.

Hepatitis A is a viral infection that affects the liver. Vaccination prepares immune memory without giving you hepatitis A. Immunity lowers the chance of illness, but it does not treat an infection that is already present and it does not protect against other types of viral hepatitis.

Some people need tailored advice, including people with reduced immune function, chronic liver disease, or a possible recent exposure. If you cannot remember receiving the vaccine, do not rely on symptoms to judge immunity: bring any vaccination record to a clinician or vaccination service. A blood test is not routinely needed for everyone, but a clinician may discuss testing when the result would change care.

Check your vaccination record and tell the clinician about travel, household contact with someone who has hepatitis A, work-related exposure, liver disease, pregnancy, allergies and medicines that affect immunity. Ask whether your previous product and vaccination timing provide the protection you need.

If a dose was missed or the record is incomplete, a clinician can make a catch-up plan. Do not restart a course on your own. After a possible exposure, seek advice promptly because post-exposure options are time-sensitive and depend on your health and vaccination history.

Until you have received personalised advice, wash hands carefully after using the toilet and before preparing food. Avoid preparing food for other people if you feel unwell or have been told you may have hepatitis A.

Contact a healthcare professional if you develop marked tiredness, nausea, loss of appetite, feeling generally unwell, abdominal discomfort, pale stools, dark urine or yellowing of the eyes or skin. These symptoms can have several causes; they do not by themselves show whether you have hepatitis A or whether the vaccine worked.

Seek prompt advice after close contact with a person who has hepatitis A, especially if you have liver disease or reduced immune function. A clinician may arrange a liver function test or other assessment and explain how to reduce spread while the cause is being clarified. Urgent care is appropriate for confusion, severe dehydration, or rapidly worsening illness.

You could ask: Do my records show enough hepatitis A vaccination? Do I need another dose or a blood test? Was I recently exposed, and should I be assessed now? Does my liver condition or medication change the advice? What symptoms should make me stay away from food preparation or seek help?