Harald zur Hausen, virologist who won the Nobel Prize for his work on cervical cancer – obituary

Harald zur Hausen, who has died aged 87, won the Nobel Prize in Medicine in 2008 for identifying the virus which can cause cervical cancer – the second most common cancer among women around the world.

When zur Hausen first began his research in the late 1960s, the sexual revolution was in full swing. Correspondingly, rates of sexually transmitted diseases such as herpes were on the rise.

Concern over the risk to public health was further amplified when a study from the Baylor College of Medicine in Texas found a link between cervical cancer and the herpes virus; women with cervical cancer were statistically more likely to be carrying antibodies indicating a previous herpes infection.

Zur Hausen, however, had his doubts. In 1972, aged 36, he took up a position as professor of virology at the University of Erlangen-Nuremberg in Bavaria, and started looking for other possible culprits, including the human papillomavirus (HPV).

This virus, which has scores of different types, is extremely common – affecting up to 80 per cent of sexually active people – and often causes no symptoms at all. The most visible sign of an infection can be genital warts, so zur Hausen decided to start there.

Using highly sophisticated molecular methods to detect the presence of HPV DNA, he and his researchers managed to identify the strain of the virus which leads to warts, HPV 6, but their research soon hit a dead end as that particular type was not found in cervical cancer.

Disappointed but not deterred, zur Hausen adapted his methods to look for strains of HPV in human tumours. By 1983 he had found three others – HPV types 11, 16 and 18. The following year his team successfully cloned the last two, allowing other scientists to conduct detailed studies of the virus’s cancer-causing properties and begin work on developing an effective vaccine.

Subsequent research found that HPV types 16 and 18 are present in 70 per cent of all cervical cancer cases worldwide. Once inside the body, the virus replicates itself by entering the DNA of its host’s cells and hijacking the normal repair functions, causing genetic mutations that can, in some cases, lead to cancer.

From September 2008, all British schoolgirls aged 12-13 were given the option of vaccination against HPV-16 and HPV-18. In 2017 the World Health Organisation called for all countries to introduce the HPV vaccine nationwide.

The youngest of four children, Harald zur Hausen was born in the city of Gelsenkirchen, North Rhine-Westphalia, on March 11 1936. His father Eduard had broken off his studies in agronomy to serve as an officer in the First World War and had met his future wife Melanie while stationed in Riga in 1919. Twenty years later Eduard enlisted again, but suffered a serious heart attack in 1944 and was released from service.

He returned home to find Gelsenkirchen under heavy bombardment from the Allied Forces. Anxious for the family’s safety, the parents agreed to send their three youngest children to a rural area south of Bremen (the eldest boy, Manfred, was being held as a prisoner of war by the Americans).

The whole family survived the war, though their home in Gelsenkirchen was looted and damaged during the bombardment. Harald attended the local school from the age of 10 and completed his secondary education in Vechta, north-western Germany. He received his medical degree from the University of Bonn, writing his thesis on the antiseptic properties of floor wax.

In 1965, while working at the University of Düsseldorf, he recovered a letter from a waste paper basket. It was an appeal for a German research fellow willing to take up a position in the virus diagnostic laboratory of the Children’s Hospital of Philadelphia.

Zur Hausen wrote back and was accepted to work with Werner and Gertrude Henle, an expatriate couple who had written scores of papers together. They had just identified a link between Burkitt’s lymphoma – a cancer which mostly affects men and boys – and the Epstein-Barr virus, and wanted to know more about how the two interacted.

It was the beginning of zur Hausen’s interest in how viruses can affect human chromosomes. Returning to Germany, he was eventually able to demonstrate how Epstein-Barr could enter a host cell and disrupt its DNA, leading to malignancies such as Burkitt’s lymphoma. His findings on “viral DNA integration and persistence” were published in the science journal Nature in 1970.

Despite this scientific pedigree, however, his relative youth counted against him when he came to question the prevailing belief that the herpes virus played a role in the development of cervical cancer. A speech he gave at a medical convention in 1974, pointing the finger at the HPV, met with a hostile silence. “It was still a crime to raise doubts,” he later observed.

Further frustration was to come. The World Health Organisation did not formally recognise the link between HPV and cancer until the 1990s, and the pharmaceutical industry was slow to roll out a vaccine.

Even when the vaccine emerged, it proved prohibitively expensive for women on low incomes and beyond the reach of most in the developing world. In a piece for Journal of the National Cancer Institute in 2001, zur Hausen decried the “costly” delay in the light of the 400,000 people who receive a cervical-cancer diagnosis every year.

Harald zur Hausen served as scientific director of the German Cancer Research Centre from 1983 to 2003. He was editor in chief of the International Journal of Cancer from 2000 to 2009, and became president of German Cancer Aid, a not-for-profit organisation.

In later years much of his research was dedicated to exploring the possible link between colon cancer and the consumption of red meat, specifically beef that has been insufficiently well-cooked. He suggested that there might be a cancer-causing virus in cattle that is resistant to the heat of cooking.

However he refused to let the prospect put him off his dinner, observing that “at my age, any type of consumption of dangerous food doesn’t play a role any more.”

Harald zur Hausen’s first marriage ended in divorce. He married, secondly, Ethel-Michele de Villiers, a fellow researcher specialising in human papillomaviruses. There were three children from the previous marriage.

Harald zur Hausen, born March 11 1936, died May 28 2023