An sudden spike in hepatitis A infection in several European countries has led to public health authorities issue urgent advisories and roll out containment strategies. The multicountry outbreak, spanning Austria, Czechia, Hungary, and Slovakia, has already infected more than 2,000 people since January 2025. The European Centre for Disease Prevention and Control (ECDC) confirmed on Friday that two genetically linked strains of the hepatitis A virus (HAV) are behind this multicountry outbreak, which alarms for ongoing community transmission and potential cross-border spillover.Though hepatitis A is generally a preventable viral illness, its comeback in Europe is a grim reminder of how vaccination gaps, sanitation flaws, and outreach failures can prove lethal — particularly for older people and those who are vulnerable.This outbreak, characterized by two similarly linked hepatitis A virus (HAV) strains, has not only affected local groups but also infected tourists traveling to popular tourist destinations in Europe. The problem is further complicated by reports of confirmed cross-border transmissions, with Germany reporting cases genetically associated with those in Austria and Hungary, indicating the likelihood for wider spread.The cluster is focussed in four middle European countries: Slovakia (880), Czechia (600), Hungary (530), and Austria (87). Although all these countries have suffered the majority of the infections, cases that had the outbreak strain are also found within Germany, reflecting the virus's capacity to transcend borders via social networks and travel.Nine fatalities have been reported to date — six in Czechia and three in Austria — underlining the potentially serious health impact of the disease, especially in older people or those with existing liver disease. The ECDC's rapid risk assessment also verifies genomic evidence of regionally linked transmissions, triggering a coordinated EU response.What is Hepatitis A?Hepatitis A is acute viral disease of the liver due to the hepatitis A virus (HAV). In contrast to its more persistent cousins, hepatitis B and C, hepatitis A does not result in chronic liver disease. But it can nevertheless generate full-blown disease and death—particularly among those at high risk.The virus is mainly spread by ingestion of infected food or water, or direct contact with an infected person. HAV is found in the feces of infected individuals and is thus majorly a factor of poor sanitation and hygiene that leads to outbreaks. The illness quickly spreads in communities lacking clean water, safe food, and proper healthcare.Contrary to hepatitis B and C, hepatitis A does not develop into chronic liver disease. Nevertheless, it may cause severe liver complications and even death in some people. Severity escalates with age. The ECDC has estimated the risk of serious illness as high in people older than 40 years and very high in individuals with pre-existing liver disease or weakened immunity.Symptoms and Challenges in Early DetectionNot all people who get hepatitis A develop symptoms. But if symptoms do occur, they might include:Weakness and fatigueAbdominal pain and feverJaundice, or yellow eyes and skinClay-colored stools and dark urineNausea and loss of appetiteDiarrhea and joint painSince the virus takes weeks to manifest as symptoms, people may spread the virus unknowingly during incubation. That timing makes it harder to track the infections and contain possible routes of exposure.Who Is Most at Risk?Although anyone can get hepatitis A, there are groups that are more likely to suffer from severe illness. The ECDC states that individuals aged 40 years and older are at greater risk of developing serious complications, and the risk increases with age. Patients with existing liver disease and those who are immunosuppressed are especially at risk, as are older persons.Social determinants also come into play. The epidemic has hit disproportionately hard among those living in homelessness, those who inject or use illicit drugs, and those living in filthy conditions or with limited healthcare access. These individuals usually do not have the resources necessary to receive vaccination or be at a hygiene standard to avoid infection.For the population at large in the affected nations, risk is at present estimated as low to moderate. Yet, the situation is dynamic, and the risk for further transmission cannot be ruled out.Slovakia has been struggling with hepatitis A since 2022, making it the epicenter of the current outbreak. Its 880 cases this year represent the largest burden across the affected nations. Czechia, meanwhile, has seen a significant jump in cases in 2025, including the majority of the deaths.Even with the fewer cases reported, there have been three deaths in Austria — highlighting the fact that the virus does not have to be widespread to pose a threat. In Hungary, more than 500 cases of infection have been reported this year, leading health authorities to increase surveillance and prevention measures.How the Virus Is Spreading?Genetic sequencing has shown that the current outbreak is being fueled by person-to-person transmission in interconnected social networks and geographic regions. The fact that genetically similar strains were detected in Germany, where it is not an epicenter, is a testament to the ease with which the virus can travel across borders—particularly in an age of high mobility and international travel.Though foodborne transmission cannot be ruled out, available evidence implicates close personal contact and unsatisfactory sanitation as main movers. This underscores the pivotal role that focused prevention and swift response play in high-risk populations.The ECDC has called on member states to carry out epidemiologic studies, expand targeted contact with high-risk groups, and improve access to vaccination. Cross-border coordination has also been highlighted by the agency, since the outbreak does not respect geography or citizenship. Strategies that are recommended include:Targeted vaccine campaigns among high-risk groupsPost-exposure prophylaxis (PEP) of close contactsIncreased sanitation and hygiene in settlements and communitiesIncreased genetic testing to track spread of virusPublic education and awareness to increase early reporting and vaccination ratesECDC's head of One Health Unit Ole Heuer highlighted the need for increased outreach: "This outbreak is a reminder that hepatitis A infection can lead to severe illness and death, particularly in individuals with poor access to health care and basic hygiene. Vaccination and sanitation services need to reach those who are most vulnerable."How You Can Protect Yourself?For people, the best defense against hepatitis A is vaccination. The hepatitis A vaccine is given in two doses, usually six to twelve months apart. The CDC says getting the vaccine — or immune globulin treatment — within two weeks of infection can ward off illness. Other important prevention measures are:Washing hands frequently with soap and water, particularly before mealsDrinking clean, filtered water and avoiding suspect food sources while abroadNot getting direct exposure to the body fluid of infected peopleThe CDC also advises travelers to countries with outbreaks of hepatitis A to get vaccinated before they go.As the peak travel season for summer draws near, it's a time of vigilance for public health officials and travelers alike. Vaccination, education, and enhanced sanitation are the pillars of prevention—not only for hepatitis A, but for the countless infectious diseases that still threaten global health security.