Hepatitis A is most common in parts of Africa, Asia, and the Middle East, where poor sanitation and limited access to clean water allow the virus to spread easily. In many of these regions, over 90% of children are infected before age 10. The virus also circulates at intermediate levels across Central and South America and eastern Europe, while Western Europe and the United States have consistently low rates.
Regions With the Highest Rates
The countries with the highest hepatitis A exposure tend to cluster in sub-Saharan Africa, the Middle East, and South and Southeast Asia. The virus is considered endemic across nearly all of Africa except South Africa. In rural Egypt, antibody testing shows that essentially 100% of the population has been exposed. Libya follows a similar pattern: 60 to 70% of three-year-olds test positive for hepatitis A antibodies, and by age seven the rate reaches 100%.
The Middle East carries some of the world’s highest seroprevalence numbers. In parts of Iran, between 85% and 99% of the population shows evidence of past infection depending on the province. Iraq’s estimated population-wide antibody rate is around 96%. Yemen’s Aden province sits at roughly 87%, and studies among Kurdish refugee populations from Turkey and Iraq found a 94% prevalence rate. North African countries follow the same trend: Tunisia reports rates between 84% and 92%, and Algeria reaches 96%.
In Southeast Asia, a cross-sectional study in rural Laos found that about 63% of people tested positive for hepatitis A antibodies, with rates varying sharply by district, ethnicity, and education level. Parts of South Asia, including India and Bangladesh, are also classified as high-endemicity areas.
Why Sanitation Is the Driving Factor
Hepatitis A spreads through contaminated water and food, or through close contact with an infected person. The single strongest predictor of how common it is in a given area is the quality of water, sanitation, and hygiene infrastructure. In rural Laos, communities that had any level of improved sanitation (even basic systems) had roughly 40% lower odds of hepatitis A exposure compared to communities practicing open defecation. Education played a role too: adults who completed upper school or university had 40 to 60% lower odds of past infection than those with no formal schooling.
Undercooked meat also contributes. In the same Laos study, consuming undercooked meat raised the odds of hepatitis A exposure by about 50%. Ethnic minorities in the study had significantly higher infection rates, likely reflecting disparities in living conditions and hygiene practices rather than any biological difference. These patterns repeat globally: wherever overcrowding, limited plumbing, and untreated water overlap, hepatitis A thrives.
Intermediate-Risk Countries and the Paradox of Improvement
Countries classified as intermediate endemicity include parts of Central and South America, eastern Europe, and portions of Asia that have undergone rapid economic development. These nations sit in an unusual epidemiological position. As sanitation improves, fewer children encounter the virus in early childhood, when infections are almost always mild or completely symptom-free. That sounds like good news, and in the long run it is. But in the short term, it creates a growing population of teenagers and adults who never developed natural immunity.
This matters because hepatitis A becomes more severe with age. When an outbreak hits a population of unexposed adults, the result is a spike in symptomatic illness: jaundice, fatigue, nausea, and occasionally liver failure. Countries in this transitional phase can actually see an increase in reported hepatitis A cases and hospitalizations even as their overall hygiene standards rise. The solution is vaccination, which several of these countries have begun incorporating into childhood immunization schedules.
Low-Risk Countries Are Not Risk-Free
Western Europe, the United States, Canada, Australia, and Japan all have low hepatitis A endemicity. Most cases in these countries trace back to international travel, imported food, or specific outbreak clusters. The global food trade has made this connection more direct: between 2012 and 2018, multiple outbreaks in developed countries were linked to food products imported from endemic regions, including frozen berries, shellfish, and sun-dried tomatoes.
Travelers to high-endemicity countries face particular risk if they are unvaccinated. The virus has an incubation period of 2 to 7 weeks, so symptoms often don’t appear until well after someone returns home. When they do appear, illness typically lasts less than 2 months, though some people feel unwell for up to 6 months. Vaccination before travel is highly effective and provides long-lasting protection.
Who Faces the Greatest Risk
Your risk depends primarily on where you live and whether you’ve been vaccinated or previously exposed. In high-endemicity countries, nearly everyone encounters the virus in childhood and carries lifelong immunity as a result. The people most vulnerable to serious illness are unvaccinated adults in transitional or low-endemicity countries, especially those who travel to endemic regions, eat raw or undercooked shellfish, or live in areas experiencing localized outbreaks.
Within any country, the pattern holds at a local level. Rural communities with limited water treatment carry higher rates than nearby urban areas with modern infrastructure. Lower education levels and lower household income correlate with higher exposure, not because of personal behavior but because of the infrastructure gap. Hepatitis A is, at its core, a disease of inadequate sanitation, and its global map reflects that reality with striking consistency.