(Edits 31st par to remove reference to website)

By Kate Kelland

LONDON, March 13 (Reuters) - The emails, tweets and blog posts in the "abuse" folder that Michael Sharpe keeps on his computer continue to pile up. Eight years after he published results of a clinical trial that found some patients with chronic fatigue syndrome can get a little better with the right talking and exercise therapies, the Oxford University professor is subjected to almost daily, often anonymous, intimidation.

A Twitter user who identifies himself as a patient called Paul Watton (@thegodofpleasur) wrote: "I really am looking forward to his professional demise and his much-deserved public humiliation." Another, Anton Mayer (@MECFSNews), likened Sharpe's behaviour to "that of an abuser."

Watton and Mayer have never been treated by Sharpe for their chronic fatigue syndrome, a little-understood condition that can bring crushing tiredness and pain. Nor have they met him, they told Reuters. They object to his work, they said, because they think it suggests their illness is psychological. Sharpe, a professor of psychological medicine, says that isn't the case. He believes that chronic fatigue syndrome is a biological condition that can be perpetuated by social and psychological factors.

Sharpe is one of around a dozen researchers in this field worldwide who are on the receiving end of a campaign to discredit their work. For many scientists, it's a new normal: From climate change to vaccines, activism and science are fighting it out online. Social media platforms are supercharging the battle.

Reuters contacted a dozen professors, doctors and researchers with experience of analysing or testing potential treatments for chronic fatigue syndrome. All said they had been the target of online harassment because activists objected to their findings. Only two had definite plans to continue researching treatments. With as many as 17 million people worldwide suffering this disabling illness, scientific research into possible therapies should be growing, these experts said, not dwindling. What concerns them most, they said, is that patients could lose out if treatment research stalls.

A spokesperson for Twitter said the platform "exists to serve the public conversation. Its strength lies in providing people with a diversity of perspectives into critical issues – all in real-time." Where someone used anonymity for bad purposes, Twitter would take immediate action, the spokesperson added.

Chronic fatigue syndrome, also known as myalgic encephalomyelitis, or CFS/ME, is described by specialists as a "complex, multisystem, and often devastating disorder." Symptoms include overwhelming fatigue, joint pain, headaches, sleep problems and isolation. It can render patients bed- or house-bound for years. The Centers for Disease Control and Prevention, or CDC, estimates the illness costs the U.S. economy $17 billion to $24 billion annually in medical bills and lost incomes. It is thought to affect as many as 2.5 million people in the United States.

No cause has been identified, no formal diagnosis established and no cure developed. Many researchers cite evidence that talking therapies and behavioural approaches can help in some cases. Yet some patients and their advocates say this amounts to a suggestion that the syndrome might be a mental illness or psychosomatic, a notion that enrages them. They would prefer that research efforts focus on identifying a biological cause or diagnosis.

One of those leading the campaign against research into psychological therapies for CFS/ME is David Tuller, a former journalist with a doctor of public health degree from University of California, Berkeley. Tuller, who describes himself as an investigator, not a campaigner, told Reuters he wants to help CFS/ME patients.

Crowdfunded by a global band of CFS/ME sufferers, their families and patient activists, Tuller has since October 2015 published more than 140 blog posts amounting to tens of thousands of words attacking studies of psychological treatments and conferences that have showcased them. He's recently complained to the CDC, New York's Columbia University and Netflix. In 2018, Netflix ran a docu-series about CFS/ME patients. It said it wanted to show the difficulties of patients "suffering from elusive and misunderstood illnesses."

Tuller refers to researchers who explore and test treatments for CFS/ME that feature a psychological element as "insane" and a "cabal" suffering from "mass delusion." They are bent on pursuing "bogus and really terrible research," he told Reuters.

Sharpe no longer conducts research into CFS/ME treatments, focusing instead on helping severely ill cancer patients. "It's just too toxic," he explained. Of more than 20 leading research groups who were publishing treatment studies in high-quality journals 10 years ago, Sharpe said, only one or two continue to do so.

The world's largest trials registry, clinicaltrials.gov, indicates that over the past decade there has been a decline in the number of new CFS/ME treatment trials being launched. From 2010 to 2014, 33 such trials started. From 2015 until the present, the figure dropped to around 20. This decline comes at a time when research into ways to help patients should be growing, not falling, because the condition is more widely recognised, scientists interviewed by Reuters said.

Reuters spoke to three specialists in CFS/ME in Britain, Denmark and the Netherlands who have reported receiving online abuse but continue to work in the field. The specialist in the Netherlands, a psychologist who works at a chronic fatigue treatment centre, said that a few years ago, research teams there had five treatment studies looking at cognitive behavioural therapies for CFS/ME patients. Now, they have no treatment studies at all. Junior researchers are wary of entering the field because of the abuse they've seen others suffer, said the specialist in Britain, a doctor who spoke on condition of anonymity.

Per Fink, a professor at the Research Clinic for Functional Disorders at Denmark's Aarhus University Hospital, said he kept going because he didn't want to let down patients, some severely ill, who are "open to any treatment that may help them."

UNCERTAINTY

The term myalgic encephalomyelitis was first used in 1956 to describe a condition associated with post-illness fatigue among patients at London's Royal Free Hospital. Thirty years later, the name chronic fatigue syndrome was coined. Now, the combination term CFS/ME is used by most people – patients, doctors and researchers – and by the U.S. National Institutes of Health.

The trigger for the condition is not known, although it can follow a bout of severe illness or extreme physical endurance, or a viral infection such as glandular fever. There is no biomarker or blood test to establish diagnosis, and patients often face misunderstanding from family, friends and doctors. Patient advocates say the condition has a history of being dismissed as "yuppie flu" or plain indolence.

With no pharmacological or physiological treatments on the horizon, scientists and doctors explored psychiatry and psychology for ways to ease the symptoms. Some patients and campaigners say that diverted attention and funding away from scientific efforts to define what causes CFS/ME and how it can be properly diagnosed.

Simon Wessely, a professor of psychological medicine at King's College London and former president of Britain's Royal College of Psychiatrists, said he decided to stop conducting research into treatment approaches for CFS/ME several years ago because he felt the online abuse was detracting from his work with patients.

But he is still the subject of what he calls "relentless internet stalking." Recent tweets directed at Wessely include one accusing him of playing "pathetic ego driven games" with the lives of people with CFS/ME, another saying "Wessely is a dangerous and evil individual" and another saying "We die, b/c of u."

Wessely's employers at King's College London have taken advice on the potential risk and have instituted X-ray scans of his mail, he says. "Everything I say and do in public, and sometimes even in private, is pored over and scrutinised," he said.

Wessely's experiences are echoed by Aarhus University Hospital's Per Fink, who runs a clinic that offers patients exercise and talking therapies.

Fink said he and the organisers of a conference he addressed at Columbia University in New York in October 2018 were hounded by complaints and protests from CFS/ME activists. A petition calling for Fink to be disinvited was signed by 10,000 people. Tuller – who in his blog wrote that the person who invited Per Fink to speak at the conference must be "uninformed or stupid or both" – called Fink a "scary guy" whose methods had "destroyed families." Tuller urged readers of his blog to go to the Columbia conference and demonstrate.

Describing himself as a doctor and researcher "who just does my job in an attempt to help people," Fink told Reuters his trip to New York was worse than anything he's experienced before. "They are scaring people away," he said. "Doctors don't want to speak about it – they try to keep a low profile. And many researchers and clinicians say they won't go into this area of therapy because it's so difficult."

SOCIAL MEDIA SUPERCHARGE

The idea of critics or activists challenging researchers and seeking to hold science to account isn't new. Most researchers say they are happy to engage in discussion. But with social media, email and internet now accessible from almost every home, mass communication gives online activists a voice with unprecedented power. In the field of CFS/ME research, it's often personal. Those at the centre of it say it's gotten out of control.

"The toxicity of it permeates everything," Sharpe told Reuters.

The campaign to have evidence-backed treatments discredited was "doing a terrible disservice to sufferers from this condition," said Wessely. "Patients are the losers here."

At the heart of the attacks on Sharpe, Wessely and other chronic fatigue treatment researchers is a study known as the PACE trial, which sought to evaluate the effectiveness of different types of therapy in CFS/ME patients.

Published in The Lancet medical journal in 2011, the results found that cognitive behavioural therapy – designed to help patients change their thinking and behaviour – and graded exercise therapy – in which patients are encouraged to start from very low levels of daily activity and then incrementally raise them – are safe and moderately effective treatments for some people.

Richard Horton, the editor of The Lancet, said his journal had received emails and letters about PACE but has no plans to retract it. He said what is needed to allow for progress in any field of medical research is "an open and respectful approach by all parties to one another."

In April last year, Tuller secured $87,500 in online crowdfunding to "debunk" the PACE trial findings. He refers to the study as "a piece of crap" and "garbage" and says he is determined to see it discredited. At speaking events filmed and shown on YouTube, he has ripped up copies of the study to show his feelings about it. Tuller has also posted a 15,000 word review of it.

Tuller cut his teeth as an AIDS activist in the 1980s. Now 62, he blogs, sends hundreds of letters and emails, and travels the world giving speeches and holding meetings as supporters send him donations and praise for his CFS/ME campaign. Tuller himself hasn't conducted or published any peer-reviewed clinical trials on CFS/ME. He has co-authored a critique of PACE.

His argument is that the therapies evaluated in the PACE trial are based on a misguided hypothesis that CFS/ME patients suffer from "unhelpful" beliefs that they have a biological disease, and that their symptoms of fatigue are made worse by deconditioning due to inactivity. He also says he thinks the trial's methodology was flawed. The scientists involved reject those arguments.

"My goal is to completely discredit the PACE trial," Tuller told Reuters. "And if they have moved out of the research field, then that's great," he said of the CFS/ME researchers he's targeting. "They shouldn't be in the field. They shouldn't be doing research at all."

Tuller disputes that his campaigning amounts to harassment. In comments to Reuters in an interview and in emails, he said his criticisms are valid. And he added: "I refuse to act in the normal bounds of academia." Asked about his motivation, he said he does not have the condition. He said he had a long-time friend who was diagnosed with CFS/ME in the early 1990s but has "no other personal stake." He said his work is helping patients by "clearing out the bad science to make way for some good science," such as research into the condition's biological basis.

Another campaign, which goes by the acronym MAIMES, or Medical Abuse in ME Sufferers, operates from Britain. It has a standard letter for people to send to their local member of parliament demanding a public inquiry into the PACE trial. There's also a Facebook page called "Abuse of ME Patients by Health Care Professionals" which has some 680 followers. The page runs stories from unnamed patients who accuse Sharpe and others of harming sufferers by calling them "lazy" and forcing them to exercise when they can't.

The campaigner and doctor behind MAIMES, Sarah Myhill, has posted YouTube videos setting out her views: "I liken it to child abuse," she says in one that has been viewed more than 8,000 times. "This amounts to a form of abuse, because these people" – CFS/ME patients – "do not have the energy to defend themselves." Myhill has published several books advocating what she calls a "naturopath's" approach to treating symptoms of CFS/ME – one using a tailored combination of nutrition, rest and medicines. She hasn't published peer-reviewed research on the efficacy of her approach.

Myhill told Reuters that she had complained to the General Medical Council – the body that maintains the official register of medical practitioners in the UK – about Sharpe and other scientists involved in the PACE trial, but her complaint was rejected. Myhill showed Reuters the letter she received from the General Medical Council. It said it was "not able to identify any issues which would require us to open an investigation" into the researchers. Contacted by Reuters, the Council did not elaborate.

As well as dissuading researchers from working in the CFS/ME field, scientists fear that pressure from campaigners has also begun to show in the wording of guidance for patients and doctors from national health authorities. In the United States, the CDC has removed references to cognitive behavioural therapy and graded exercise therapy from its website.

The head of the CDC's chronic viral diseases branch, Elizabeth Unger, told Reuters this was done to remove jargon and medical terms that are not widely understood by the public. "We received feedback that the terms were confusing and too frequently misinterpreted," she said in an email response to questions.

Unger said the CDC's advice stresses that each CFS/ME patient's needs are different. "For some, carefully managing exercise and activities can be helpful," she said. "Likewise, some patients may find that talking with a therapist helps them."

In Britain, government guidelines on treating CFS/ME published by the National Institute for Health and Care Excellence (NICE), currently recommend cognitive behavioural therapy and graded exercise. But these too are under review, due to be revised and republished by 2020. A source close to NICE told Reuters the agency had been subjected to "a lot of lobbying" aimed at getting it to review the guidelines "and in particular to change recommendations around graded exercise therapy and cognitive behavioural therapy." The source declined to go into detail about who was behind the lobbying.

Publishers, too, are feeling the heat. In a move described as "disproportionate and poorly justified" by the researchers involved, editors of the Cochrane Reviews science journals said in October that they would be temporarily withdrawing a review that analysed evidence from eight studies on exercise therapy for CFS/ME patients.

Cochrane Reviews evaluate the best science on a given subject and are considered a gold standard in scientific literature. The review in question, led by a Norwegian research team and published by Cochrane in April 2017, had concluded there was moderate quality evidence to show that "exercise therapy had a positive effect on people's daily physical functioning, sleep and self-ratings of overall health."

Tuller told Reuters in emails in October that he considered the Cochrane Review to be "fraught with bias" and said its authors have bought into "delusions that these studies (the ones they reviewed) represent good science." After hearing news of the review's temporary withdrawal, Tuller said he'd had a "long meeting" with Cochrane editors in Britain last summer, and had "pressed them hard." "So did others," he said.

Cochrane's editor in chief, David Tovey, confirmed that he had met with Tuller, but said the meeting had nothing to do with his decision to temporarily withdraw the review. He said complaints about the review from patients and campaigners had raised "important questions" about how the review was conducted and reported which he and his fellow editors felt needed to be addressed.

Lillebeth Larun, a scientist at the Norwegian Institute of Public Health who led the Cochrane Review, is one of several scientists who vociferously disagreed with Tovey's decision to withdraw it. For her, the move is a sign that the activists who have plagued her for years have now got to her editors. In the decade or so that she's been conducting research in this area, she told Reuters, she's endured online attacks and abusive emails, and at various points had to take a break from working due to the pressure. Returning to a CFS/ME project would make her feel physically sick with anxiety.

"Attempts to limit, undermine or manipulate evidence based results, pressure or intimidate researchers into or away from any given conclusions, will ultimately have a negative effect," she told Reuters. "It will only lead to those researchers choosing to work in other areas and reduce the resources dedicated to providing the help patients so desperately need."

Some CFS/ME patients disagree. Reuters contacted the Twitter user who identifies himself as Paul Watton to ask him about his online attacks. Speaking by phone, Watton said he has been ill with CFS/ME and unable to work in his former job as a builder for 15 years, and feels let down by the medical establishment. Reuters was unable to independently verify his account.

"I agree entirely with what David Tuller says," Watton told Reuters. "This is a chronic illness for which there is – currently – no curative treatment."

In Britain there are at least 50 specialist chronic fatigue syndrome services that treat around 8,000 adults each year under government guidelines, offering behavioural and psychological therapies. Research published in July 2017 showed around a third of adults affected by the illness who attended these specialist clinics reported substantial improvement in their health. In the survey, more than 1,000 patients were asked about fatigue, physical function, general function, mood, pain and sleep problems before and after getting the services.

Colin Barton, chairman of the Sussex and Kent CFS/ME Society – a patient group in southern England – said talking therapies and graded exercise helped him recover to the point that he can lead an almost normal life. He told Reuters that in his experience, patients who talk about having been helped by psychological or graded exercise therapies come in for abuse just like the researchers. They face accusations that they were never ill in the first place; that their condition was misdiagnosed; and that their recovery is therefore fake, he said. As a result, he said, many recovering or recovered CFS/ME patients feel forced to withdraw from the debate. (reporting by Kate Kelland; editing by Janet McBride and John Blanton)

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