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Brian Vastag remembers the moment he was hit with the infection that changed his life.

“It started very suddenly — July 8, 2012, at 9:30 in the morning,” he said. “It was almost like a switch. It was a sudden fever and dizziness.”

Dr. David Goldstein of the NINDS tests Brian Vastag for autonomic nervous system dysfunction as part of a myalgic encephalomyelitis study. ME patients often suffer dizziness when standing. A tilt-table test helps measure this. Beth Mazur

Five years later, Vastag is taking part in an intense experiment aimed at finding out if and how that infection may have disrupted his nervous system, leaving him with myalgic encephalomyelitis, commonly known as chronic fatigue syndrome, or ME/CFS.

It’s a study that will take volunteers into the frontiers of medical science. Their cells will be used to make genetically engineered mice with human immune systems, and their blood cells will be turned into nerve cells using a transformative technology that’s still the stuff of science journals.

Vastag is spending two weeks at the National Institutes of Health outside Washington, D.C., undergoing an intense battery of tests. He has been providing blood, spinal fluid and urine samples. He’s taking grip tests and getting X-rays. He will undergo magnetic resonance imaging and functional MRI to see what’s happening in his brain — there're also neurocognitive tests, exercise tolerance tests, as well as tests of the autonomic nervous system, the immune system and metabolic function.

"They haven’t received the attention they deserve because most of the tests don’t show anything.”

Usually, medical studies take a look at one particular aspect of a disease. But this study overseen by Dr. Avindra Nath is looking at every conceivable aspect of a condition that many people still don’t believe is a real disease.

Nath and his team will transform the blood cells of their volunteers — turning them back into a primitive state called induced pluripotent stem cells (iPS cells) and then redirecting them to form nerve cells — to study as a proxy for the brain and nerve cells that cannot be ethically removed from a living patient.

“I am very convinced by these patients. Their complaints are very real,” said Nath, clinical director of the NIH’s National Institute of Neurological Disorders and Stroke (NINDS).

“But they haven’t received the attention they deserve because most of the tests don’t show anything.”

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Nath is not the only expert who is convinced. In 2015, a committee appointed by the Institute of Medicine (now renamed the National Academy of Medicine) said CFS needed a new name to distance it from the stigma of being an imaginary illness.

“The committee recommends that this disorder be renamed ‘systemic exertion intolerance disease’ (SEID),” the panel of experts said. They estimated that between 836,000 and 2.5 million Americans have a disorder falling under the definition.

The naming recommendation hasn’t had much pickup, but Nath hopes to get to the bottom of at least some of the mystery. He is recruiting 40 ME/CFS patients plus 20 healthy patients, along with 20 people who have recovered from Lyme disease — an infection that can cause long-term symptoms that often overlap with CFS/ME.

Nath has limited the study to people who develop their symptoms after an infection and he is trying to keep his volunteers as similar to one another as possible. It’s possible ME/CFS is not a single disease with a single cause, and he believes that may be throwing researchers off.

Dr. Avindra Nath, a neurologist at the National Institute of Neurological Disorders and Stroke, examines Brian Vastag as part of a study Nath is conducting into the causes of myalgic encephalomyelitis. Beth Mazur

Nath is deploying his expertise on the links between infections and the immune system to try to find out whether an infection may have somehow altered the immune system, whether some people have a genetic susceptibility to certain viruses or bacteria, or whether it’s in fact a persistent infection or a change in a patient’s natural population of microbes — the microbiome — that is causing the symptoms.

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They want to more precisely define the condition and its symptoms.

For Vastag, these symptoms have been profound.

“There is and was for me exhaustion, utter exhaustion after doing things,” Vastag said as he leaned back in a hospital bed in the NIH’s flagship Clinical Center hospital.

“My long-term memory is mostly intact. Working memory — it’s not there any more.”

“I couldn’t even watch TV. Any noise could be painful.”

Vastag, a 45-year-old former Washington Post science reporter, said his case is fairly typical.

After his sudden illness, instead of getting better in about a week, Vastag continued feeling tired and feverish for months. Neuropathy — a tingling and numbness — started in his foot and moved to other limbs.

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He uses a reporter’s landmarks to remember the timeline. The first week in October is when the Nobel Prizes for science and medicine get awarded and, like many reporters on the science beat, Vastag was up early to report on the winners in 2012.

“I was sitting there looking at my computer screen and the lines of text started moving around. There were shimmery, swimming lines of text,” he said. “It was terrifying.”

He had trouble reading after that. “I was struggling to keep the life I had been building in Washington, D.C.,” he said. “It was like my brain had gone to another dimension where nothing was working any more.”

Being a reporter, he tried to find explanations for his symptoms. “I thought I had multiple sclerosis. It was terrifying. At some point I was worried about ALS.” ALS or amyotrophic lateral sclerosis is a degenerative nerve disease that eventually completely paralyzes patients, killing them as they lose the ability to breathe.

Vastag became unable to work and left his job. He’s now on Social Security disability.

“By early 2013, I was almost 100 percent bed-bound,” he recalled. “I had friends bring me food. I showered every 10 days.”

He went from one doctor to another with no clear diagnosis. “The physical sensation is that the body is shutting down, that the end is near,” he said.

“I couldn’t even watch TV. Any noise could be painful.” Mostly, he slept.

Vastag signed up to be evaluated for rare diseases at NIH. Reading about something called myalgic encephalomyelitis, Vastag realized the symptoms being described matched his.

He says there are some clear clues that someone has ME/CFS, including abnormal immune cell function.

Exercise tests also show it, Vastag said. Most people quickly adapt to exercise. If they push hard one day, the next day it will be a little bit easier. CFS/ME patients don’t. “We don’t compensate for exercise,” he said. Vastag, who once enjoyed 20-mile bike rides, struggled to finish seven minutes on an exercise cycle.

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The next day would be even worse. “Your anaerobic threshold goes down on the second day,” Vastag said. “It is a sign your energy production system has been damaged.”

He moved to Hawaii, where he could rest away from the stress of city life and where he could share a small space with a fellow ME/CFS patient. Vastag tried taking long-term antivirals and has done a little self-hacking after exploring ME/CFS websites and forums — for instance, inhaling insulin in a self-treatment approach that some patients say helps them to think more clearly.

“I feel there has been this ‘don’t go there’ sign around here.”

Gradually, he has become able to cope with daily living and regained his appetite. "But I am still disabled," he said.

Vastag’s weight had plummeted from 185 pounds to 150 pounds. He’s still gaunt, four years later, but says he is up to around 160 pounds now. “Now I feel like I’ve stabilized,” he said. “I have problems with everyday life but I am not bedbound any more.”

In 2015, Vastag wrote an open letter in the Post to the NIH asking that the world’s largest funder of biomedical science allot more time and attention to ME/CFS. NIH director Dr. Francis Collins took up the challenge and authorized Nath’s study.

Dr. David Goldstein tests Vastag on a tilt-table. Beth Mazur

It’s a full-court press. The study team includes a long list of top NIH experts from the sprawling campus, including neurologists, virologists, allergists, psychologists, a cancer fatigue specialist, an expert in measuring metabolism and physical therapists.

“NIH has finally kind of opened itself up to the illness and the need of understanding this illness,” Vastag said. “I feel there has been this ‘don’t go there’ sign around here.”

Once the study is done, Nath hopes he can help establish biomarkers for ME/CFS, perhaps a certain abnormality in a certain immune cell, or a precise balance of immune system cells. That way the condition can be more precisely diagnosed and, eventually, treated.

"If I come back for part two of the study in about year, maybe I'll get to meet my mouse," Vastag said.