"It was the most startling side effect I've ever come across." That's how Elizabeth Miller, head of the immunization department at Public Health England, described some recent vaccine research you've probably never heard about: Pandemrix, a shot designed to stave off swine flu, also appears to be causing narcolepsy in some children.

Public health officials — especially ones that work in the politically fraught field of vaccine safety — don't typically make emotive statements like that.

Then Miller told me about something that shocked her even more: The media didn't pick up on this story at all. In fact, she characterized the reception to her 2013 research about vaccines and narcolepsy as "radio silence."

I told Miller that I didn't find her news all that surprising, because I ignored the Pandemrix story, too. I've sometimes shied away from writing about uncertainty in vaccine science for fear that my stories might have horrible consequences for public health. It seems other reporters may have been doing the same.

Vaccines are one of the single greatest contributors to public health of the past century. And in recent years, whenever anti-vaccine groups or cranks have tried to cast doubt on this fact, the country's best health journalists have sprung into to action, working to present the facts and essentially debunk anti-vaccine pseudoscience. Vaccines, after all, are overwhelmingly safe. And people should know that.

But what happens when credible scientists discover real drawbacks to certain vaccines? How do we report on that responsibly — without giving ammunition to deniers?

One reason the media is reluctant to report on vaccine drawbacks: We've been burned before

Miller is an extremely credible scientist, and her results didn't come in isolation. Previously, researchers in Finland and Sweden had uncovered an association between Pandemrix and narcolepsy, a chronic neurological disorder that messes up the body's ability to regulate sleep-wake cycles. So Miller and her colleagues began to investigate. They combed the health records and sleep tests of patients at British hospitals. In their 2013 study published in the British Medical Journal, they came to a firm conclusion: The swine flu vaccine increased the risk of narcolepsy in children. All told, more than 1,000 people who got the shot developed narcolepsy, an incurable condition.

In the United States, Pandemrix was never licensed, and it was only used during the 2009-'10 H1N1 swine flu pandemic — not before or after. To be clear, some reporters have since picked up on the story, particularly after manufacturer GlaxoSmithKline acknowledged the link and governments agreed to give victims compensation.

Still, there was little coverage of the early research itself. And Miller thinks there may be a reason journalists stayed away: They've been burned in the past.

Back in 1998, a doctor named Andrew Wakefield famously claimed a link between the measles-mumps-rubella vaccine and autism. As it turned out, Wakefield's study was fraudulent. The scientific evidence overwhelmingly suggests that the MMR vaccine is safe. Wakefield had distorted the evidence, and his study has since been retracted; he's also been thoroughly discredited.

But at the time, Wakefield's study received lots of breathless (and uncritical) coverage. And those news reports fueled anti-vaccine scares that drove down rates of immunization coverage in Europe and around the world, helping to bring back entirely preventable diseases like measles. This effect persists today.



"We went to the New England Journal of Medicine. They did not want to take the paper. The Lancet rejected it. The BMJ rejected it."

You can see the dilemma facing health reporters. Criticisms of vaccines have often come from cranks like Wakefield (and his celebrity sidekick Jenny McCarthy). So the media is understandably skeptical. What's more, the consequences of getting things wrong are severe — stories about vaccine drawbacks run the risk of reducing vaccination rates and creating a genuine public health crisis.

It's not just journalists, either. Many scientists now seem to be extra-skeptical toward anyone pointing out drawbacks in vaccines, according to Hanna Nohynek, a vaccine researcher with the Finnish government. She conducted some of the early research on the narcolepsy finding, and told me she had great difficulty placing her study in scientific journals.

"We went to the New England Journal of Medicine. They did not want to take the paper. The Lancet rejected it. The BMJ rejected it," she said. "Nobody wanted to publish something that might be similar [to the Wakefield paper]."

So how should reporters cover uncertainty in vaccine science?

All this heavy skepticism is understandable. At the same time, scientists and journalists can't just ignore evidence around vaccines — especially if there are real risks involved.

In search of a better way, I reached out to various researchers and reporters to get their views on how we can better cover vaccine uncertainty. They offered up a number of good suggestions that have implications for other politically charged issues in science, too:

1) It's okay to be more skeptical of newer vaccines than older, established ones. Andre Picard, the public health reporter at Canada's Globe and Mail newspaper, has navigated tricky questions around vaccines for more than 30 years. He says he still has trouble with this question. "How do you cover the side effects of vaccines without giving credence to antivax zealots? is a really good question," he wrote in an email.

Theoretically, he said, journalists should report on vaccines like any other drug: communicating both the benefits and risks. "With older childhood vaccines, that’s pretty easy," he says. "Lots of benefits, and negligible risks."

But he puts newer vaccines in a different category. As with all new drugs, there can be unknown side effects. "For example, when the rotavirus vaccine was tied to intussusception, that was an important story to cover even though it killed a vaccine with many benefits. And, thankfully, there is now a better version with fewer side effects," he says. Picard reported that story, and in 2011, the early findings about a potential narcolepsy side effect with the swine flu jab.



"If we’re going to urge people to vaccinate for the public good, then we have to help them in the rare instances when things go wrong"

Picard's advice was that we should treat newer vaccines with more skepticism until long-term safety data are in and rare side effects have had time to present themselves. "I believe that if we’re going to urge people to vaccinate for the public good, then we have to help them in the rare instances when things go wrong," he added.

This makes sense based on how vaccines are studied. Tom Shimabukuro, the deputy director of the immunization safety office of the Centers for Disease Control and Prevention, says that newer vaccines are subject to enhanced safety monitoring — the exact kind that initially picked up problems with the swine flu shot, which researchers like Miller then investigated.

"When vaccines are newly licensed and recommended, the CDC will conduct enhanced safety monitoring during the uptake phase which involves special attention to reviewing surveillance data, individual reports that come into the vaccine adverse events reporting system," he said. The agency also conducts real-time analyses of the data to spot any potentially worrisome trends or patterns as soon as they emerge.

To put this into context, vaccines go through much more rigorous scrutiny than the millions of supplements and drugs Americans take every day. But public health agencies do this because vaccines are given to perfectly healthy people. There's little tolerance for screw-ups.



Even so, testing can't always immediately pick up rare side effects, which often emerge after millions take a vaccine, as opposed to the hundreds or thousands who were studied in the trial runs before vaccines hit the market. (To give you a sense of scale, the swine flu shot was given out to 30 million people in 47 countries; just more than 1,000 are known to have developed narcolepsy.)

As Picard suggested, this early period is when journalists should be on guard for emerging problems.

2) Accurately reflect the weight of the evidence. In coverage of vaccines, it's extremely important to reflect the state of the science and avoid giving equal weight to both sides of an issue that aren't actually equal, Graham Dixon, an assistant professor with the Edward R. Murrow College of Communication at Washington State University, told me.

He reminded me of his 2012 study, which found that exposure to falsely balanced articles about an autism-vaccine link left readers with the erroneous perception that there was a controversy among scientists when there actually wasn't one. The overwhelming weight of research favored the safety and efficacy of the MMR shot. Wakefield was an extreme outlier.

"The idea of balance that journalists tend to adhere to could cause some unnecessary uncertainty around vaccines safety," Dixon explained. So when journalists need to cover uncertainty in a vaccine, they can do so by making sure to contextualize it.

With the problematic swine flu vaccine, for example, journalists (like me) could have noted that this was a new vaccine, that the emerging side effect was extremely rare, and that this finding in no way applied to all the other vaccines in current use that have never been shown to cause narcolepsy. That would perhaps be a better alternative to the "radio silence" Miller described.

3) Avoid cheerleading for vaccines. Given all the controversy around vaccination in the United States in recent years, many of the most esteemed public health reporters in the country have taken to mounting vigorous defenses of vaccines, cheerleading for everything from the flu shot to the HPV vaccine.

Dixon warned against this.

In fact, he even felt that today's vaccine coverage is too one-sided. "I think that comes at the expense of including minority views," he added. He explained that the minority views in autism-vaccine debate were simply based on bad science and not worthy of attention. But what about newer vaccines, like Pandemrix, where the evidence shows the vaccine may be harmful to some?

"The findings [about Pandemrix] were based on rigorous research practices and have since been replicated by a number of independent scholars to the point that the CDC issued a statement about it," he said.

"I think we’re doing a disservice to the public in not reporting on things that potentially are real side effects," he added. "It worries me that journalists are adopting this attitude, 'We want to be pro-vaccine, and anyone who talks about something anti-vaccine, we want to ostracize them' — when there might be legitimate issues that come up, in the case of narcolepsy and Pandemrix."

Brendan Nyhan, an assistant professor at Dartmouth, echoed Dixon, saying that both journalists and the public need to learn to be able to hold two contradictory thoughts about vaccines in their heads at the same time.

"There is good scientific consensus on the safety and efficacy of vaccines," Nyhan said, "but there may be cases where, with newer vaccines" there may be safety problems. Ignoring early warning of signs and reporting uncritically means reporters and scientists aren't fulfilling their public service duty.

Responsible reporting on vaccine uncertainty can save lives

Reporters should also know that while irresponsible reporting on vaccines can have adverse effects, responsible reporting can be incredibly valuable.

Hanna Nohynek said that one of the reasons the problems with Pandemrix came to light was because some journalists in Finland actually began sounding alarms about the vaccine. Media reports about patients who fell ill after getting the shot helped to encourage scientists like her to investigate.

"The media had been strongly pinpointing that new vaccines aren't fully safe when they're started to be used on a large scale. In some sense, the media is right — these are extremely rare events linked to vaccines," she said.

That's important, because the rare side effect could not have been detected in vaccine studies before the shot went to market. "We would have had to study 300,000 Finnish people in order to see the signal. There's no way you could do such trials," she said. She now credits the Finnish media with pushing the conversation forward.

A case study: Revisiting some recent media stories on the HPV vaccine

Nohynek's story reminded me of a recent report in the Toronto Star about the HPV vaccine. In that case, well-meaning reporters at that paper used several anecdotes about people who thought they had been harmed by the HPV vaccine as proof of danger — and then reported them without including the crucial context that millions of women have been safely vaccinated. The packaging of the final story was completely sensational.

A wonder drug's dark side: A Star investigation looks into the HPV vaccine Gardasil. #health http://t.co/tJolD8HCY9 pic.twitter.com/iU3bF1zNbJ — TorontoStar (@TorontoStar) February 5, 2015

That was a bad story. But there was a better, more accurate story to tell about this particular HPV vaccine — namely, that this shot has been on the market for 10 years, and it's possible that rare side effects could still emerge. This is the case for any newish medical treatment.



This month, the European Medicines Agency launched an inquiry into the safety profile of the HPV vaccine. "The review does not question that the benefits of HPV vaccines outweigh their risks," the EMA said in a news release. Rather, the agency said it's gathering data on rare reports of two conditions — a chronic pain condition called complex regional pain syndrome (CRPS), and postural orthostatic tachycardia syndrome (POTS), which increases the heart rate and causes dizziness and fainting — to see if there's a link with the HPV vaccine.

So far, no one else has been able to identify a link between these side effects and the shot. One 2009 analysis of adverse events reports, for example, shows the vaccine is no more harmful than any other. In other words, it's incredibly safe. That's the same finding as the largest-ever overview of all the available safety data on the vaccine from 2006 to 2015, published in the Pediatric Infectious Disease Journal. 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 venous thromboembolic adverse events.

A story that accurately described what we know about a possible link between HPV vaccines and rare disorders could be quite useful — as long as it's placed in full context and avoids fearmongering with unproven anecdotes. "They are very, very few cases in comparison to what gains you have with the vaccine that’s been on the market since 2006 and given to over 70 million women," says Nohynek. "To me it’s a signal that has to be looked into, but it doesn't mean we should stop giving the HPV vaccine."

That's a more nuanced tale than one we're used to about vaccines. But it's the kind of story reporters and scientists need to get used to telling, and one that audiences need to be receptive to.