A 2016 hepatitis A outbreak among gay men across Europe exposed how many vaccine gaps existed in the community. What health authorities recommend, how the vaccination works, and where to start.
An outbreak that exposed vaccine gaps
Starting in mid-2016, health authorities tracked a hepatitis A outbreak spreading across Europe among men who have sex with men. In Berlin alone, Germany's Robert Koch Institute counted more than 80 cases between late 2016 and mid-2017, over 95 percent of them men older than 20, with a median age of 32. Across Europe, the ECDC reported roughly 1,500 infections in 16 countries, with especially high case counts in the UK, Italy, Spain, Germany, and the Netherlands. When German investigators traced the Berlin cases, they found that the long-standing vaccine recommendation for this group simply hadn't reached most of the people it was meant for.
Hepatitis A spreads through the fecal-oral route: tiny traces of stool reaching the mouth. During sex, the risk rises mainly through oral-anal contact. Condoms offer little protection here, since transmission doesn't primarily happen through semen or blood but through direct skin and mucosal contact. That's exactly why hepatitis A is hard to prevent through safer-sex counseling alone. Vaccination is the most effective protection available.
What health authorities recommend
The CDC recommends hepatitis A and B vaccination for all gay and bisexual men, regardless of specific risk factors, since infection rates run higher in this group. Vaccination can be given as separate hepatitis A and hepatitis B shots or as a combined vaccine, typically following a 0-1-6 month schedule (a first dose, a second one month later, a third six months later). A single hepatitis A dose already provides solid protection within two to four weeks, according to outbreak-response guidance from German health authorities; the second dose, six to eighteen months later, secures long-term immunity.
Hepatitis B spreads sexually, including through unprotected sex, and health authorities likewise flag gay and bisexual men as a group with elevated exposure risk. Adults without prior vaccination typically need three doses on the same 0-1-6 month schedule. Since 2022, a two-dose option (Heplisav-B) has also been available for adults, with doses spaced at least one month apart. Testing antibody levels four to eight weeks after the final dose can confirm the vaccine worked; once protection is confirmed, most healthy adults don't need routine booster shots.
Two viruses, two different courses
Hepatitis A and B get mentioned in the same breath so often that it's easy to miss how differently they behave. Most people who get hepatitis A recover fully within weeks and gain lifelong immunity afterward, though the illness itself can bring nausea, jaundice, and weeks of exhaustion, and hits harder in people with existing liver disease. There's no chronic form of hepatitis A. Hepatitis B is different: in some people, especially those infected as infants or young children, it becomes chronic. That risk is lower for adults but not zero. Left untreated, chronic hepatitis B can lead to cirrhosis or liver cancer over years. That distinction is why both vaccines are recommended independently of each other, even though a combination shot can cover both at once.
Where to get vaccinated
Primary care doctors, sexual health clinics, and many community health centers offer hepatitis vaccination, often during the same visit as a PrEP checkup or STI screening. If you don't know your vaccination status, a blood test can check for existing immunity first, though testing isn't required before getting vaccinated. People living with HIV can safely receive both vaccines. Anyone recently exposed to an infected person should get vaccinated within two weeks, since the shot can still prevent infection at that stage.
Coverage rules vary by country and insurance plan, so it's worth checking with a local provider or health department about cost before booking an appointment. In the US, hepatitis A and B vaccines are covered under the Affordable Care Act's preventive care provisions for most insurance plans; other countries fund these shots through public health programs targeting specific risk groups.
Why this still matters
The major 2016-2017 outbreak has faded from headlines, but the underlying problem, vaccine gaps in a group that's specifically recommended to get vaccinated, hasn't gone away on its own. Because hepatitis A and B have become fairly rare overall, indication-based vaccinations for specific risk groups are easy for both patients and doctors to overlook unless someone actively brings it up. If you don't know your status, the next routine health visit, PrEP appointment, or travel booking to a region with higher hepatitis A prevalence is a good moment to check.
Frequently asked questions
Last reviewed: 21. August 2026
