Steve Johnson still can't believe a cold sore virus landed him in the emergency room.
He had blacked out and rolled his Ford F250 truck on a rural Washington state road last May. Disoriented, he couldn’t describe what had happened. The emergency physician suspected a traumatic brain injury, while the on-call neurologist said MRI images suggested a tumor. But an infectious disease consultant realized something else was going on: a common infection was causing an illness so unusual that neither of his colleagues recognized it.
Johnson had encephalitis, a dangerous inflammation of the brain, caused by herpes simplex virus type 1 (HSV-1) — the same organism that causes cold sores.
While HSV-1 infects more than half of the U.S. population, according to the Centers for Disease Control and Prevention, herpes simplex encephalitis affects only a few hundred Americans a year, experts estimate.
But rare, it's devastating when the virus travels to the brain. Nearly a year after his sudden attack, Johnson, now 60, is mostly recovered, though he fought fatigue and nausea for months and his memory is unreliable. He remains stunned that he got sick at all — and that he was lucky enough to survive an infection that kills one of every four victims and leaves two out of four neurologically impaired.
“I used to get fever blisters, three or four times a year, if I got a bad cold or the flu or was stressed,” he said from his home in Carson, Wash. “It is mind-boggling that something so minor could migrate to the brain and change your life this much.”
Johnson wasn’t having a cold sore outbreak when encephalitis struck him. Most people who develop the disease do not, said Dr. Richard Whitley, the Loeb Scholar in Pediatrics at the University of Alabama and a recognized expert on herpes encephalitis, known as HSE. But the disease arises from the same conditions that cause cold sores: Either a new infection with herpes virus, or the sudden re-awakening — known as “reactivation” — of a herpes infection from where it lies dormant in nerve fibers near the spine.
Mystery as to why it leads to encephalitis
What causes the virus to reactivate — and what determines whether a reactivation causes cold sores or encephalitis — remains something of a mystery, Whitley said.
Johnson is a sturdy guy, a former state parks ranger whose love of the outdoors led him to a post-retirement job in a fly-fishing shop 20 miles from home. His unexpected ordeal began with a bad headache. His wife, Arlene, got him Tylenol, and he said he felt better. But two days later, still worried, she stopped by the shop in mid-afternoon to see how he was doing, only to find his boss had already sent him home because he seemed nauseated and confused.
“I called him on the way, said I wanted to take him to the doctor, and he said OK,” she recalled. “I got home before him. I’m waiting, calling his phone, but he didn’t answer. Then I heard sirens.”
Johnson had taken his exit, but failed to recognize his street and looped back toward the highway instead. He doesn't recall what happened next. Paramedics pulled him from the crushed truck, which had narrowly missed a natural-gas line, and took him to Southwest Washington Medical Center in Vancouver, Wash. There, Dr. Joseph Kane recommended Johnson receive antibiotics and the antiviral drug acyclovir while they waited for results from a spinal tap, bacterial cultures and screening for viral DNA.
About 3,000 cases of encephalitis are diagnosed in the U.S. every year. The condition can be triggered by a number of viruses, but HSV-1 is believed to be the most common single cause — though that is hard to say for sure, since in many cases the virus causing the illness is never identified. Kane’s medical center sees one to two HSE cases each year, and his department prefers to start treatment preemptively, knowing they can stop if tests come back negative. Johnson’s were negative for bacteria, positive for HSV-1.
“We know if a person has lapsed into a coma prior to initiation of effective antibiotics, their prognosis for full recovery is impaired,” Kane said. “More often than not, we are starting acyclovir on people who don’t need it. But this way people who do need it get it, and we have not had a patient with herpes encephalitis who was left with a profound deficit.”
Any one who experiences a high fever, headache and disorientation should see a doctor, Whitley said: “We know there are other things that cause these symptoms, including some drugs. It’s important to be seen quickly, so we can figure out whatever is needed to do.”
In Johnson’s case, his medical team did exactly the right thing — but not all do, because herpes encephalitis is so seldom recognized, said Whitley.
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“It often takes a family member to recognize that something improper is going on,” he said.
'Everyone thinks I'm fine and I'm not'
That was true for Ingrid Guerci, also 60, of Tarrytown, N.Y., who developed what she thought was the flu in December 1995. A headache and high fever put her in bed for several days, but her husband, George, realized something else was wrong when Ingrid, who smoked Marlboros, told him she was going outside for “a mustard.” He drove her to the ER, where the staff thought she was having a stroke — until a neurologist whose professional partner had died of encephalitis recognized her symptoms and ordered a course of acyclovir.
Guerci was in the hospital for two weeks and on disability for three months; it took eight months before she was strong enough to work full-time. Fifteen years later, she still struggles with ringing in her ears, sensitivity to light and memory problems. “People say, ‘Oh, you’re getting older, that’s normal,’” she said. “But it isn’t normal; it happened overnight. It’s frustrating that everyone thinks I’m fine and I’m not.”
HSE is not contagious, strictly speaking: Someone suffering from encephalitis cannot pass it to someone else. In 10 to 15 percent of cases, though, a patient with HSE may start shedding the herpes virus from the tissues of their mouth and throat, even though they have no evidence of a cold sore. In that case, they could pass herpes infection to someone else, just as a cold sore can.
That shedding state is one of the not-yet understood aspects of the disease, Kane said, one of several mysteries that make HSE both difficult to predict and almost impossible to prevent.
Though awareness is important, “people shouldn’t worry” about HSE, even if they suffer from cold sores, Kane said. “This is an incredibly uncommon disease.”
Maryn McKenna is a freelance journalist who specializes in infectious disease, public health, global health and food policy. She is the author of "Superbug: The Fatal Menace of MRSA" and "Beating Back the Devil."
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