The research led by Dr. zur Hausen into the human papillomavirus, or HPV, turned a theory that was once on the fringes of scientific acceptance into new fields of ontological study and potentially spared tens of thousands of people from getting cancer.

His findings also offered insights into the role of HPV in a range of sexually transmitted cancers in women and men — accounting for about 5 percent of all cancer cases worldwide.

Dr. zur Hausen faced a wall of skepticism at the beginning. He “went against the current dogma,” said the 2008 announcement of the Nobel Prize in medicine, which Dr. zur Hausen shared with two French researchers for their work in identifying HIV, the virus that causes AIDS.

As Dr. zur Hausen began his research in the 1970s, most cancer specialists believed cervical cancer was mostly triggered by factors such as hormones or heredity. Pap smears had made early detection possible and mortality rates were falling.

Report: HPV test better than Pap smear in early cancer detection

Dr. zur Hausen’s idea was built on how other viruses, such as Epstein-Barr, can increase the risk of cancers in lymph nodes and elsewhere. There was anecdotal evidence to give Dr. zur Hausen a start. Many women diagnosed with cervical cancer also had genital warts caused by HPV. Yet establishing a connection took years of painstaking detective work in the lab.

The first problem was that there was no method at the time to grow HPV in tissue cultures. “It’s like starting a car to see how fast it will go. If you can’t get the motor started, you don’t know,” Wayne Lancaster, a microbiologist at Georgetown University, told The Washington Post in 1985.

In addition, finding research funding was difficult. The few researchers who supported Dr. zur Hausen thought he was looking in the wrong direction. Most believed a herpes virus, HSV-2, could be a link to cervical cancer.

Step after step, Dr. zur Hausen built his evidence. He and his team hunted for genetic markers of HPV in cancer cells. A hospital donated biopsy samples for their first tests.

By 1984, he had published two studies confirming strains of HPV in cervical cancer clusters — showing a pathway for most cervical cancer cases. Dr. zur Hausen’s work also helped launch studies that found HPV links to other cancers in male and female genitalia or passed to other parts of the body through sexual contact.

“I’m not sure vindicated is the right word because English is not my first language,” he told the Globe and Mail in Toronto in 2008. “But I feel that we did indeed follow the right path despite what others were saying.”

Two years earlier, in 2006, the Food and Drug Administration had approved the first HPV vaccine, which was recommended for young girls as well as boys. More than 75 percent of U.S. boys and girls under 17 have at least one dose of the HPV vaccine, according to the Centers for Disease Control and Prevention. (Cervical cancer rates in the United States have dropped, with about 13,000 new cases a year and about 4,000 deaths, the CDC said.)

Worldwide, however, the percentage of girls with at least one dose fell from 20 percent in 2019 to about 15 percent in 2021, the World Health Organization reported. Cervical cancer was blamed for about 342,000 deaths around the world in 2020.

Many public health officials attribute the rates to the relative high cost of the vaccine, growing anti-vaccine activism and cultural complications, such as physicians and parents refusing to discuss sex-related issues with girls.

“Some of them are really religious reasons … This is only part, probably, of the reasons of those people,” Dr. zur Hausen said. “But it’s a disaster if you look at it from a public health viewpoint.”

Childhood in war

Harald zur Hausen was born March 11, 1936, in Gelsenkirchen in western Germany, where his parents settled after being forced to leave what is now Latvia in 1919 during the Russian Revolution. His father, who had gone to the Baltics on the promise of land by the German-speaking community, served in the German military during World War II. His mother was a homemaker.

Allied air raids pounded Gelsenkirchen, a hub for coal production and factories. “Bombing raids came closer and closer,” Dr. zur Hausen recalled. Schools were closed, and he wandered the forests and fields, developing a keen interest in nature and early dreams of becoming a naturalist.

After the war, his father took the family to northern Germany, where Dr. zur Hausen resumed school and struggled to catch up after years away from a classroom. He enrolled in the University of Bonn in 1955 to study medicine. He transferred twice — to the University of Hamburg and then the University of Düsseldorf Medical Academy — before receiving his medical degree in 1960. He later completed training in gynecology and obstetrics.

In the mid-1960s, he took a position at the Virus Laboratories of Children’s Hospital of Philadelphia, working alongside virologists Werner and Gertrude Henle, who had fled Nazi Germany. Their research into the Epstein-Barr virus, and its potential raise cancer risks, introduced Dr. zur Hausen into the nascent field of tumor virology.

“Despite the fact that both had been German immigrants harboring very bad memories of their last years in Germany, they opened their lab for many German postdocs almost instantly after World War II,” wrote Dr. zur Hausen.

He returned to Germany in 1969 to join the University of Würzburg’s Institute for Virology as a professor and researcher. In 1972, he moved to the University of Erlangen-Nuremberg. Five years later, he became head of the department of virology and hygiene at the University of Freiburg.

The Nobel Committed cited Dr. zur Hausen’s affiliation with the German Cancer Research Center in its announcement of the award. His published works included a book, “Infections Causing Human Cancer” (2006).

Survivors include his wife of 30 years, Ethel-Michele de Villiers, a former researcher at the German Cancer Research Center; and three sons from an earlier marriage.

His Nobel stirred an unusual ethics probe behind the decision. A member of the Nobel Assembly that selected the recipients, Bo Angelin, was also a board member of the Anglo-Swedish drugmaker AstraZeneca. The company acquired a company that produced a component used in HPV vaccines and received royalties on the vaccine sales. A Swedish prosecutor opened an investigation but found no wrongdoing.

Dr. zur Hausen avoided any public comment on the matter and instead used much of his time as an advocate for the HPV vaccine. Even in the home country, however, he faced resistance from anti-vaccine groups that grew more militant during the pandemic.

“Not being vaccinated,” he said, “is playing with fire.”