Why Japan’s HPV vaccine rates dropped from 70% to near zero

A doctor who has been battling anti-vaccine campaigners in Japan just won a prestigious award for standing up for science.

Riko Muranaka, of Kyoto University, was awarded the 2017 John Maddox prize for her work uncovering the pseudoscience at the heart of widespread fear in Japan about the HPV vaccine. The prestigious prize is awarded each year by the journal Nature, the Kohn Foundation, and the charity Sense about Science, to a person who promotes sound evidence in the face of hostility.

Muranaka’s story explains how vaccine panic takes off — and how hard it can be to undo, even with the best-intentioned efforts.

In Japan, coverage rates for the HPV vaccine have plummeted from 70 percent in 2013 to less than 1 percent today. This happened after a preliminary (and allegedly fraudulent) mouse study showing the vaccine caused brain damage was spread by the media, along with unconfirmed video reports of girls in wheelchairs and having seizures after getting immunized.

Anti-vaccine groups also blamed the shot for causing chronic pain and heart and neurological troubles. The government didn’t help matters when it decided to suspend proactive recommendations for HPV vaccines, despite finding no evidence to support the claims parents and anti-vaccine groups were making.

To be clear, the HPV vaccine is recognized by public health and scientific groups around the world as a safe and effective tool for preventing cancers. In the US, it’s recommended for boys and girls ages 9 to 26.

There’s no good data suggesting there are significant safety concerns caused by the HPV vaccine. The largest-ever overview of all the available safety data on the vaccine from 2006 to 2015, published in the Pediatric Infectious Disease Journal, as well as another BMJ study involving about a million girls in Denmark and Sweden, found there was no association between the vaccine and a range of harms, including autoimmune, neurological, and cardiovascular adverse events. The European Medicines Agency also recently looked at the scientific evidence and found no link between the vaccine and the pain and other symptoms people are attributing to it.

“There are now accumulated safety studies that include several million persons and which compare the risks for a wide range of health outcomes in vaccinated and unvaccinated subjects,” the World Health Organization’s Global Advisory Committee on Vaccine Safety said in June. Yet “despite the extensive safety data available for this vaccine, attention has continued to focus on spurious case reports and unsubstantiated allegations.”

In Japan, the suspect anti-vaccine research was credulously spread by the media, along with those videos of girls purporting to be harmed. The combination of the bunk study and parental fears seems to have won out over science.

Here’s where Muranaka comes in. In 2015, she started to write about the HPV vaccine in Japanese newspapers, hoping to draw attention to the science supporting the vaccine. In 2016, she investigated the mouse study. The study’s author, a prominent doctor named Shuichi Ikeda, had been claiming that the vaccine was harmful based on research about mice brains, which purported to show that rodents injected with the vaccine had suffered brain damage. He’d show slides from the study on TV programs, spreading the preliminary data, which had never been replicated in humans.

What happened next was incredible, and it shows how important asking for evidence is. According to Cornell’s Alliance for Science,

When Muranka [sic] finally tracked down the source of the slide, the researcher involved told her the experiment had involved only one mouse being injected with each vaccine, and that the mouse brain showed by Ikeda was not even the one injected with HPV vaccine.

Muranaka also discovered that the mice vaccinated in the experiment had been genetically modified and produced an auto-antibody naturally during aging. Serum full of the antibody was taken from these mice, sprayed on brain sections of normal mice and photographed to show “brain damage” supposedly caused by HPV vaccine.

Taking on the science fraud wasn’t easy, and that’s why Muranaka won the Maddox prize. Ikeda, the scientist, is now claiming defamation, and the fallout has caused Muranaka to lose her regular newspaper columns and book deal. She told the BBC that she’s also endured personal threats and threats on her family.

Even so, she says the battle has been worth it. On accepting the prize, she said, “I simply cannot ignore dangerous claims that threaten public health. I want people to hear the truth, that’s the reason I continue to write and speak out.”

Unfortunately, Muranaka’s investigations haven’t turned Japan’s HPV situation around yet. Coverage rates for the HPV shot remain below 1 percent. Because of the anti-vaccine propaganda, millions of young Japanese people won’t be getting a shot that could prevent them from getting cancer, Muranaka added in an interview with Science.

“Each year in Japan, 27,000 to 28,000 women are diagnosed with cervical cancer and around 3,000 die,” she said. “HPV vaccines can prevent this disease. Yet because of the campaigners’ videos and the government’s decision to suspend recommending the vaccine, many mothers and children do not know this vaccine is safe. The long-term impact will be preventable suffering and death.”