STOCKHOLM >> Americans Harvey J. Alter and Charles M. Rice and British-born scientist Michael Houghton jointly won the Nobel Prize for medicine today for their discovery of the hepatitis C virus, a major source of liver disease that affects millions worldwide.

Announcing the prize, the Nobel Committee noted that the trio’s work identified a major source of blood-borne hepatitis that couldn’t be explained by the previously discovered hepatitis A and B viruses. Their work, dating back to the 1970s and 1980s, has helped saved millions of lives, it said.

The medicine prize carried particular significance this year due to the coronavirus pandemic, which has highlighted the importance that medical research has for societies and economies around the world — and the damage that a single virus can wreak on the planet.

“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 committee said.

“Their discovery also allowed the rapid development of antiviral drugs directed at hepatitis C,” it added. “For the first time in history, the disease can now be cured, raising hopes of eradicating hepatitis C virus from the world population.”

WHO estimates there are over 70 million cases of hepatitis C worldwide and 400,000 deaths from it each year. The disease is chronic and a major cause of liver cancer and cirrhosis requiring liver transplants.

Alter carried out his prize-winning studies at the U.S. National Institutes of Health in Bethesda, where he remains active, the committee said. Rice worked on hepatitis at Washington University in St. Louis and now works at Rockefeller University in New York. Houghton, born in Britain in 1950, studied at the Chiron Corporation in California before moving to the University of Alberta in Canada.

Alter described the 4:45 a.m. phone call he got from Stockholm as “the best alarm clock I’ve ever had.” He said he ignored the first two times the phone rang before “angrily” answering it the third time, adding that his anger went away “in about a second.”

“It’s so kind of other-worldly,” he said. “It’s something you don’t think will ever happen and sometimes you don’t think you deserve it to happen and it happens.”

“In this crazy COVID year where everything is turned upside down, this is another nice upside down for me,” he added.

Alter described the journey to identifying hepatitis C as a decades-long effort. In a 1988 poem he wrote, “Let us see this elusive virus/If we don’t publish soon/They’re going to fire us!”

Rice told The Associated Press that at first he thought the call today from the Nobel committee was a crank call. He said the work he and his colleagues did produce a way to grow the virus in the lab and develop a test to screen the blood supply.

“We take it for granted that if you get a transfusion, you’re not going to get sick from that transfusion,” he said. “That was not the case before, but is certainly the case now.”

At a media briefing today, Rice said that while “winning a prize is one thing,” being able to witness people being successfully treated with drugs to eliminate hepatitis C within about three decades of the discovery of the disease was “the greatest reward.” “It’s a rare treat for a basic scientist,” he said.

He predicted that with recent advances in genetic sequencing and other technologies, the world would soon have more tools, including drugs and vaccines, to stop the coronavirus pandemic.

“The rate at which people have been able to understand (COVID-19) … is just spectacular,” he said. “I’m very optimistic about the future of this.”

John McLauchlan, a professor of viral hepatitis at the University of Glasgow, called the three laureates “pioneers” and said their discovery made the global elimination of the disease possible. In 2016, the World Health Organization issued a strategy to wipe out the disease by 2030.

“That would mark the first time we might possibly control a viral infection using only drugs,” McLauchlan said.

Will Irving, a virologist at the University of Nottingham, said identifying hepatitis C had been the “holy grail” in medicine.

“After hepatitis A and B were discovered in the 1970s, it was clear there was still at least one other virus or more that were causing liver damage,” he said.

“We knew there was a virus in the blood supply, because when people had blood transfusions they would get liver damage,” Irving said. “It was recognized as a risk but there was nothing we could do. We didn’t know what the virus was and we couldn’t test for it.”

Nobel Committee member Patrik Ernfors drew a parallel between this year’s prize and the current rush by millions of scientists around the world to find a vaccine to combat the coronavirus pandemic.

“The first thing you need to do is to identify the causing virus,” he told reporters. “And once that has been done, that is, in itself, the starting point for the development of drugs to treat the disease and also to develop vaccines against the disorder.”

Unlike hepatitis A, which is transmitted via food or water and causes an acute infection that can last a few weeks, hepatitis B and C are transmitted through blood.

American scientist Baruch Blumberg discovered the hepatitis B virus in 1967 and received the 1976 Nobel Prize in medicine, but this did not explain all cases of chronic hepatitis, a disease that was becoming more common even in healthy people who had received or given blood.

“Before the discovery of the hepatitis C virus, it was a bit like Russian roulette to get a blood transfusion,” said Nobel Committee member Nils-Goran Larsson.

Alter discovered that plasma from patients who didn’t have hepatitis B could also transfer the disease.

“The breakthrough came in 1989, when Michael Houghton and colleagues working at Chiron Corporation used a combination of molecular biology and immunology-based techniques to clone the virus,” said Nobel Committee member Gunilla Karlsson-Hedestam.

Later, Rice confirmed that a cloned hepatitis virus alone could cause persistent infection in chimpanzees and reproduce the disease observed in humans.

The hepatitis C virus belongs to a group known as flaviviruses that also includes West Nile virus, dengue virus and yellow fever virus.

Graham Foster, professor of hepatology at Queen Mary University, said the discovery of hepatitis C had prevented millions from getting sick or dying of the disease or other liver problems.

Foster said the discovery had a significant impact both in developing countries, like Egypt and Pakistan, where millions were infected via contaminated medical equipment or procedures, and in developed countries like the U.S., where the blood supply itself was often contaminated.

“This discovery allowed for safe blood transfusion and it allowed the rapid development of treatments for hepatitis C,” Foster said.

The Nobel Committee often recognizes basic science that has laid the foundations for practical applications in common use today.

“It takes time before it’s fully apparent how beneficial a discovery is,” said Thomas Perlmann, the Secretary-General of the Nobel Committee. “Of course these serological tests have been around for quite a while, but the antiviral drugs that emerged as a consequence of this significant discovery have been much more recent.”

The prestigious Nobel award comes with a gold medal and prize money of 10 million Swedish kronor (over $1,118,000), courtesy of a bequest left 124 years ago by the prize’s creator, Swedish inventor Alfred Nobel.

Today’s medicine award is the first of six prizes this year being announced through Oct. 12. The other prizes are for outstanding work in the fields of physics, chemistry, literature, peace and economics.