Hepatitis is one of the most widespread infectious diseases on the planet. Combining all five types (A through E), hundreds of millions of people are currently infected worldwide, and viral hepatitis kills roughly 3,500 people every day. It ranks as the second leading infectious cause of death globally, on par with tuberculosis.
Global Numbers by Type
The five hepatitis viruses vary enormously in how many people they affect, how they spread, and whether they cause short-term or lifelong illness.
Hepatitis A is the most common acute form. An estimated 159 million infections occurred in 2019 alone. Most people recover fully within weeks, and the virus does not cause chronic disease. It spreads through contaminated food and water, so it’s far more common in regions with limited sanitation.
Hepatitis B is the most common chronic form. The WHO estimates that 254 million people were living with chronic hepatitis B in 2022. Many were infected at birth or in early childhood, which is when the virus is most likely to become a lifelong infection. Hepatitis B caused an estimated 1.1 million deaths in 2022, mostly from cirrhosis and liver cancer that develop over decades.
Hepatitis C affects roughly 50 million people worldwide. It spreads primarily through blood-to-blood contact, including shared needles and, in some countries, unsafe medical procedures. Unlike hepatitis B, hepatitis C can now be cured with a course of antiviral medication that takes 8 to 12 weeks, but only about 36% of people living with the virus know they have it.
Hepatitis D only infects people who already have hepatitis B. Among all chronic hepatitis B carriers, roughly 4.5% also carry hepatitis D. That percentage climbs to about 16% among people being treated at liver disease clinics, because the combination of both viruses accelerates liver damage and leads to more severe disease.
Hepatitis E is similar to hepatitis A in that it spreads through contaminated water and is usually a short-term illness. It’s most common in East and South Asia. In most healthy adults it resolves on its own, though it can be dangerous during pregnancy.
How Common Hepatitis Is in the United States
The U.S. has far lower rates than many parts of the world, thanks to widespread vaccination, blood supply screening, and cleaner water infrastructure. Still, the numbers are not small.
In 2023, the CDC estimated about 3,300 hepatitis A infections across the country, a sharp drop from the large outbreaks that occurred from 2016 to 2020. Hepatitis B accounted for an estimated 14,400 new acute infections, plus 17,650 newly reported chronic cases. Hepatitis C was the largest contributor, with an estimated 69,000 new acute infections and over 101,500 newly reported chronic cases in a single year.
These reported numbers almost certainly undercount the true burden. Many hepatitis B and C infections cause no symptoms for years or even decades, so people carry the virus without knowing it. The gap between actual infections and reported cases is especially wide for hepatitis C: the CDC recorded about 5,000 confirmed acute cases but estimates the true number was closer to 69,000.
Who Is Most Affected
In the U.S., acute hepatitis B rates in 2023 were highest among adults aged 40 to 49, at 1.4 cases per 100,000 people. Rates were also elevated in the 50 to 59 age group (1.2 per 100,000). Cases among people under 20 were essentially zero, reflecting the success of routine childhood vaccination that began in the early 1990s.
Hepatitis C trends look different. New infections have risen sharply among younger adults in their 20s and 30s, driven largely by injection drug use tied to the opioid crisis. At the same time, a large pool of chronic infections exists among people born between 1945 and 1965, who were exposed decades ago before the virus was even identified and blood donations could be screened. That’s why universal hepatitis C screening is now recommended for all adults at least once in their lifetime.
Globally, the highest burden of chronic hepatitis B sits in sub-Saharan Africa and the Western Pacific region, where mother-to-child transmission remains common. Hepatitis C is most concentrated in Central and East Asia, North Africa, and the Middle East.
Why So Many Cases Go Undetected
Both hepatitis B and C can remain silent for 20 to 30 years. The viruses quietly damage liver cells without producing noticeable symptoms until the disease has progressed to cirrhosis, liver failure, or cancer. This is why hepatitis is sometimes called a “silent epidemic.”
For hepatitis C, only about one in three infected people worldwide has been diagnosed. The remaining two-thirds have no idea they carry the virus. This matters because hepatitis C is curable, and treatment prevents the liver damage that leads to death. Every undiagnosed person is also a potential source of new infections.
Hepatitis B diagnosis gaps are similarly wide in many low- and middle-income countries where testing infrastructure is limited and stigma discourages people from seeking care.
The Global Push to Reduce Cases
The WHO has set a target to eliminate viral hepatitis as a major public health threat by 2030. That means reducing new infections by 90% and deaths by 65% compared to 2015 levels, bringing annual new infections below 520,000 and deaths below 450,000. Progress so far has been uneven. Hepatitis B vaccination in infants has expanded dramatically, but access to testing and treatment for both hepatitis B and C remains limited in the countries where the burden is highest.
Viral hepatitis currently kills 1.3 million people per year. That number has actually increased in recent years even as deaths from HIV, tuberculosis, and malaria have declined, making hepatitis an outlier among major infectious diseases. The gap between available tools (effective vaccines for hepatitis A and B, a cure for hepatitis C) and the number of people who actually receive them remains the central challenge.