Hepatitis A and B Vaccine: How Long It Lasts, Side Effects, NHS Guide, and Booster Information
The single most-asked question about the hepatitis A vaccine is how long it lasts — and the answer is significantly more reassuring than most people expect. Once the full two-dose course is completed, protection is expected to last at least 25 years and is probably indefinite, according to current UK Health Security Agency (UKHSA) guidance. Here is the complete guide to hepatitis A and B vaccines: how long each lasts, when to get a booster, who gets them free on the NHS, side effects, and everything about the combined Twinrix vaccine.
This article is for educational and informational purposes only. Consult your GP, pharmacist, or travel clinic for advice specific to your health and travel plans.
How Long Does the Hepatitis A Vaccine Last?
This is the question driving the vast majority of searches on this topic — and the evidence-based answer is highly reassuring:
| Vaccination Status | How Long Protection Lasts |
| Single dose (1st dose only) | Several months — typically 6 to 12 months. Provides good short-term protection for travel. |
| Full 2-dose course completed | At least 25 years — and probably indefinite (NaTHNaC/UKHSA) |
| Research consensus (2020 review) | Studies suggest protection may last 30-40 years or provide lifetime protection |
| Booster recommended for ongoing-risk individuals | After 25 years, for those at continued risk (UKHSA guidance) |
The authoritative guidance in the UK comes from NaTHNaC (National Travel Health Network and Centre — the body that sets UK travel health standards). Their current guidance, updated to reflect March 2026 data, states: ‘The duration of protection from a completed course of hepatitis A vaccine can be expected to be at least 25 years and probably indefinite. However, UKHSA recommends that until further evidence is available on persistence of protective immunity, a booster dose at 25 years is indicated for those at ongoing risk of hepatitis A.’
The practical implication: if you completed the full two-dose course, you are protected for decades. Most healthy people who completed both doses do not need a booster during their lifetime. The 25-year booster recommendation applies specifically to people with continued high exposure risk — frequent travellers to high-risk regions, those with chronic liver disease, healthcare workers, and MSM.
How Long Does the Hepatitis A Vaccine Take to Work?
Most people develop useful protection within two to four weeks of the first dose. Some people respond faster. The first dose alone is sufficient for last-minute travellers — even if you are departing in the next few days, a single dose provides meaningful short-term protection that is better than none. The second dose given six to twelve months later is what converts that short-term protection into the long-term immunity that lasts for decades.
If you receive the hepatitis A vaccine combined with the typhoid vaccine (brands such as Hepatyrix or Viatim), the hepatitis A component still requires a separate booster dose later to achieve long-term protection — the combined vaccine primes the immune response but does not complete the full hepatitis A course.
Hepatitis A Vaccine Schedule and Booster Timing
| Dose | Timing |
| 1st dose | As soon as possible before travel (ideally 2-4 weeks minimum) |
| 2nd dose (booster) | 6 to 12 months after 1st dose (can be delayed up to 36 months if needed) |
| Long-term booster | After 25 years — only for those at ongoing risk |
An important point about the booster schedule: if you had your first dose but missed the second within the standard window, you do not need to restart the course. You can receive the booster dose even if several years have passed since the first dose — contact your travel clinic or GP. The immune system retains the priming effect of the first dose for an extended period.
How Long Does the Hepatitis B Vaccine Last?
Hepatitis B vaccination provides long-lasting protection that is considered lifelong in healthy individuals who complete the full course. Unlike hepatitis A, where booster doses are sometimes considered after 25 years, routine hepatitis B boosters are not recommended for healthy people in the UK.
The mechanism: even when measured hepatitis B antibody levels fall to low or undetectable levels over years, the immune system retains immunological memory — the ability to mount a rapid protective response on re-exposure to the virus. This is why healthy individuals who completed their course do not require routine re-testing or boosters.
Exceptions where antibody testing and boosters may be relevant:
- Healthcare workers and laboratory staff — occupational health programmes typically check hepatitis B antibody titres after the primary course and may offer a booster if levels are below a protective threshold
- People with weakened immune systems (immunosuppression, HIV, dialysis patients) — may not mount a sufficient antibody response and may need additional doses or testing
- Occupational health advice takes precedence for those in clinical roles
Hepatitis A and B Vaccine Side Effects
Hepatitis A Vaccine Side Effects
Side effects of the hepatitis A vaccine are generally mild and short-lived:
- Soreness, redness, or swelling at the injection site — the most common reaction
- Headache
- Tiredness and fatigue
- Low-grade fever
- Nausea or loss of appetite
- Mild malaise (general feeling of being unwell)
These side effects typically resolve within one to two days. Serious side effects are extremely rare. As with all vaccines, anaphylaxis is a very rare possibility — the person administering the vaccine will be trained to respond immediately.
Hepatitis B Vaccine Side Effects
Side effects of the hepatitis B vaccine are similar in character to hepatitis A:
- Soreness at the injection site
- Headache
- Fatigue
- Mild fever — may occasionally be more pronounced than with hepatitis A vaccine
- Muscle aches
Serious side effects are extremely rare. The hepatitis B vaccine has an excellent safety record from decades of widespread use worldwide.
Combined Hepatitis A and B (Twinrix) Side Effects
Twinrix is a combined hepatitis A and B vaccine. Its side effect profile is similar to the individual vaccines — injection site reactions, mild fever, headache, and fatigue are the most commonly reported effects. These are typically mild and resolve within a couple of days. Having a combined vaccine does not mean you are more likely to experience side effects than with two separate injections.
Hepatitis A and Typhoid Combined Vaccine Side Effects
Combined hepatitis A and typhoid vaccines (Hepatyrix, Viatim) can cause injection site reactions, headache, fever, and general malaise — these reflect the combined immune stimulation of two vaccines at once. These side effects are usually mild and short-lived. A key point: the combined hepatitis A and typhoid vaccine provides hepatitis A priming only. A separate hepatitis A booster dose is still required 6 to 12 months later to achieve long-term hepatitis A protection.
Hepatitis A and B Vaccines on the NHS
Is the Hepatitis A Vaccine Free on the NHS?
For most travellers, the hepatitis A vaccine is not available free on the NHS and is considered a private travel vaccine. In the UK, the NHS does not routinely fund hepatitis A vaccination for travel as a standard entitlement.
The hepatitis A vaccine is available free on the NHS for:
- People with chronic liver disease (including cirrhosis, chronic hepatitis C)
- People who are HIV positive
- Intravenous drug users
- Men who have sex with men (MSM)
- Occupationally at-risk individuals
- Travellers who fall into specific higher-risk categories — check with your GP
For those not in these groups, the hepatitis A vaccine is typically obtained from travel clinics or pharmacies offering private travel vaccinations. Costs vary: a single dose typically costs £35-£65 at UK travel clinics. Brands available include Havrix 1440 (adults) and Havrix Junior 720 (children), Vaqta, and Avaxim.
Is the Hepatitis B Vaccine Free on the NHS?
Yes — hepatitis B vaccination is free on the NHS for several groups:
- All babies as part of the routine 6-in-1 vaccination at 8, 12, and 16 weeks of age — hepatitis B has been included in the routine infant schedule since 2017
- Healthcare workers, laboratory staff, and others at occupational risk — through their employer’s occupational health programme
- Sexual health clinic patients identified as being at increased risk
- People who inject drugs — through drug treatment services and GP practices
- Household and sexual contacts of people with chronic hepatitis B
- People with chronic liver disease or who are HIV positive
The Combined Hepatitis A and B Vaccine: Twinrix
Twinrix is a combined vaccine that protects against both hepatitis A and hepatitis B in a single injection course. It is particularly convenient for travellers who need protection against both infections and want to minimise the number of injections.
| Schedule | Timing |
| Standard Twinrix course | 3 doses: months 0, 1, and 6 |
| Accelerated Twinrix course | 3 doses on days 0, 7, and 21 — plus a booster at 12 months |
| Duration of protection | Mirrors separate vaccines — long-lasting hepatitis A and B protection when course completed |
The accelerated schedule is useful for last-minute travel bookings where the standard 6-month timeline is not achievable. An extra booster at 12 months is required after the accelerated schedule to ensure full long-term protection.
Who Needs the Hepatitis A Vaccine?
Hepatitis A is spread through contaminated food and water and through contact with infected individuals. Travellers are the primary group seeking vaccination in the UK. Areas with higher rates of hepatitis A include:
- The Indian subcontinent (India, Pakistan, Bangladesh, Sri Lanka)
- Sub-Saharan Africa and North Africa
- Parts of the Far East, particularly rural areas
- South and Central America
- The Middle East
- Eastern Europe (particularly areas with poorer sanitation infrastructure)
As of March 2026, NaTHNaC has flagged active hepatitis A outbreaks in Sweden (linked to frozen imported berries), Italy — specifically Naples and Capri (linked to seafood consumption), and Hong Kong (MSM community cluster). These current alerts demonstrate that hepatitis A risk is not confined to long-haul destinations.
Beyond travel, non-travellers at higher risk include men who have sex with men, people who inject drugs, and those with chronic liver disease — these groups are eligible for NHS vaccination.
Hepatitis A Vaccine and Travel: Practical Timing
For travel protection:
- Ideally: get your first dose at least two to four weeks before departure — this gives your immune system time to build protection before you arrive at your destination
- Late booking: even if you are travelling very soon, getting the vaccine is still worthwhile — one dose provides meaningful short-term protection
- Already had your first dose but not the booster?: contact a travel clinic to receive the second dose — you do not need to restart the course regardless of how long ago you had the first injection
- Unsure whether you have been vaccinated before?: most travel clinics can review your records, or it may be safely assumed you need a course if records are unavailable
Frequently Asked Questions
How long does the hepatitis A vaccine last?
A single dose provides protection for approximately 6 to 12 months. Once the full two-dose course is completed (second dose given 6-12 months after the first), protection lasts at least 25 years and is probably indefinite according to NaTHNaC and UKHSA. A 2020 research review suggests protection may last 30-40 years or longer. A booster after 25 years is only recommended for those at ongoing high risk.
How long does the hepatitis B vaccine last?
The hepatitis B vaccine is considered to provide lifelong protection in healthy individuals who complete the full course. Even when antibody levels fall over time, immune memory provides protection. Routine boosters are not recommended for healthy people. Healthcare workers may have antibody levels checked through occupational health.
What are the side effects of the hepatitis A and B vaccine?
Both vaccines cause similar mild side effects: soreness at the injection site, headache, fatigue, and mild fever are most common. These usually resolve within one to two days. Serious side effects are extremely rare.
Is the hepatitis A vaccine free on the NHS?
Not for most travellers — hepatitis A is typically a private travel vaccine in the UK costing approximately £35-£65 per dose. It is free on the NHS for people with chronic liver disease, HIV, MSM, intravenous drug users, and others at clinical risk. Speak to your GP to check eligibility.
How long does the hepatitis A vaccine take to work?
Most people develop useful protection within two to four weeks of the first dose. Even a dose taken in the days before departure provides some protection, with immunity continuing to build after travel.
Do I need a hepatitis A booster?
If you completed both doses of the hepatitis A vaccine, you do not need a booster for at least 25 years. If you only had one dose, you should get the second dose to complete the course — contact a travel clinic or GP. The second dose can be given up to 36 months after the first without needing to restart.
What is Twinrix?
Twinrix is the combined hepatitis A and B vaccine. It is given as three doses (at months 0, 1, and 6, or on an accelerated schedule) and provides long-term protection against both infections. It is popular with frequent travellers who need both vaccines.
Final Thoughts
The hepatitis A vaccine is one of the most effective travel vaccines available, with protection from the full two-dose course expected to last at least 25 years and likely longer. The hepatitis B vaccine offers lifelong protection without routine boosters for healthy people. Both are well-tolerated with mild, short-lived side effects. For UK travellers heading to higher-risk destinations in Asia, Africa, the Middle East, or Central and South America, these vaccinations provide reliable long-term protection for all future trips — making them well worth completing the full course even if you miss the initial travel window for the second dose.This article is for educational purposes only. Consult your GP, pharmacist, or travel clinic for advice specific to your health and travel plans.