Stockholm : Two Americans and one British-born scientist now working in Canada have won the 2020 Nobel Prize in medicine or physiology on Monday for their discovery of the hepatitis C virus.

Thomas Perlmann, secretary of the Nobel Committee and professor of molecular development biology at the Karolinska Institute, announced the award at a ceremony in Stockholm.

Harvey Alter of the National Institutes of Health in Bethesda, Md., Michael Houghton the University of Alberta in Canada, and Charles Rice of Rockefeller University in New York City share the prize.

Their work has helped speed the fight against blood-borne hepatitis, a major global health problem that causes cirrhosis and liver cancer in people around the world. Their discovery has also allowed for the rapid development of antiviral drugs directed at hepatitis C.

“The discovery of hepatitis C virus was important for public health in two ways,” biochemist Jeremy Berg, professor of computational and systems biology at the University at Pittsburgh and former director of the NIH’s National Institute of General Medical Sciences, told STAT. “First, the discovery enabled testing for screening blood for the agent that was responsible for blood-borne transmission of hepatitis and liver cancer risk. Second, knowledge of the causative agent facilitated drug development, particularly protease inhibitors that can treat existing hepatitis C virus infections and cure the disease in many cases.”

“Thanks to their discovery, highly sensitive blood tests for the virus are now available and these have essentially eliminated post-transfusion hepatitis in many parts of the world, greatly improving global health,” the Nobel Prize committee said in its announcement. “For the first time in history, the disease can now be cured, raising hopes of eradicating Hepatitis C virus from the world population.”

The three laureates will share 10 million Swedish kronor, or about $1.07 million. Their names are added to a list of medicine Nobel winners that includes 222 men and 12 women.

Hepatitis, defined as liver inflammation, is usually caused by a viral infection, although alcohol misuse, environmental toxins, and autoimmune disease can also lead to the same condition. Hepatitis A comes from contaminated food or polluted water, but the illness it causes is relatively brief in duration. Hepatitis C, like hepatitis B, is a blood-borne infection, bringing acute illness to some people but chronic disease to 71 million people around the world, according to WHO estimates.

This is the second Nobel Prize awarded for a hepatitis discovery. In the 1960s, Baruch Blumberg, who identified what became known as the blood-borne hepatitis B virus, won the prize in 1976. Baruch laid the groundwork for the development of diagnostic tests and an effective vaccine.

Alter had also been studying hepatitis in patients who had received blood transfusions. Tests based on Baruch’s work could diagnose transfusion-related hepatitis B, but they still couldn’t explain a large number of cases. Tests for hepatitis A virus infection were also developed around this time, but could not account for these cases. Alter and his NIH colleagues proved that this was something different when they showed that blood from these hepatitis patients could transmit the disease to chimpanzees, the only susceptible host besides humans. Later studies determined that this infectious agent was indeed a virus and the disease was a new, distinct form of chronic viral hepatitis that became known as “non-A, non-B” hepatitis.