Doctors link polio to West Nile virus

By Stephen Smith, Globe Staff, 9/24/2002

Mosquito-borne West Nile virus is causing a medical condition rarely
seen by US physicians since the 1950s: polio.

In case reports released yesterday, stunned neurologists in
Mississippi and Georgia describe the conditions of four patients
suffering from the hobbled limbs, impaired breathing, and fevers that
are the hallmark of polio, a disease essentially eradicated in the
United States.

Just like the polio patients of the first half of the 20th century,
the West Nile victims seen this summer by the Southern doctors are
also enduring prolonged muscle weakness and respiratory ailments that
will require months of treatment and probably will disable some of the
patients permanently.

''I teach this as a historical thing to the residents,'' said Dr.
Jonathan D. Glass, director of the neuromuscular program at Emory
University in Atlanta and one of the physicians who treated the polio
patients. ''We simply don't see it today. That's why I didn't believe
it at first.''

The strain of polio that was so widely feared in the 20th century, and
now prevented by vaccines, is caused by a different virus than West
Nile. In fact, West Nile comes from a different family than viruses
known to cause the disease. However, the devastating effects are the
same.

In polio, the virus attacks the gray matter of the patients' spinal
cord, which contains the neurons responsible for carrying information
to the muscles. As the attack frays the neuron fibers, muscles turn
limp, often producing uneven results - a leg gone weak on the right
side, an arm on the left. It also results in bladder and bowel
dysfunction, along with respiratory complications that can leave
patients tethered to breathing machines.

According to the Centers for Disease Control, the West Nile virus has
killed 94 people nationwide this year, including two in Massachusetts,
and sickened 1,963, by far the largest outbreak since it was first
reported in the United States three years ago. Although other viral
illnesses kill vastly more people - the flu is blamed for 20,000
deaths annually - public-health authorities are concerned about West
Nile because it has spread from coast to coast so quickly and produced
unexpected symptoms, with polio being the most recent example.

''We obviously have to learn a lot more about this virus,'' said Dr.
Alfred DeMaria, director of communicable disease control for the
Massachusetts Department of Public Health. ''This is another aspect
that's worrisome about West Nile.''

The New England Journal of Medicine released the articles on the polio
link nearly a month before their scheduled publication, an unusual
step reserved for reports of urgent medical importance. The doctors
who wrote the articles said yesterday they believe it is vital that
their findings circulate among physicians because some of the patients
they treated had been misdiagnosed and prescribed treatments that
could have been life-threatening.

And they suspect - strongly - that other cases of West Nile-induced
polio have gone untreated and unreported. After discovering polio in
their own West Nile patients, the physicians in Mississippi and
Georgia decided to review previous outbreaks. In examining autopsy
results from New York City in 1999, the first time West Nile was
identified in the nation, the doctors uncovered symptoms that struck
them as remarkably similar to the cases they had seen this summer.

Dr. A. Arturo Leis, a neurologist at Methodist Rehabilitation Center
in Jackson, Miss., saw such a patient in late July or early August. He
recalled walking into an exam room and witnessing a 56-year-old man
who had been referred to him because of muscle weakness. In reviewing
the patient's medical chart, Leis discovered that the man had been
diagnosed weeks earlier with early signs of a stroke and prescribed
{*filter*}-thinning medication. The same man also was diagnosed with
Guillain-Barre syndrome, a disorder in which the body's immune system
attacks part of the nervous system.

Only after running {*filter*} tests, observing symptoms similar to polio,
and performing a battery of electrically activated tests that record
activity in nerves and in spinal cord cells, did the Mississippi
physicians reach their diagnosis: polio, caused by West Nile virus.

Previously, severe cases of West Nile had been characterized by
meningitis and encephalitis, the brain swelling that is regarded as
the most serious consequence of the virus. But the muscle weakness and
other problems associated with polio were not evident.

''I thought, `This is extremely unusual - this can't be,''' Leis said.
''How can a virus, in this case West Nile, change its clinical
properties to such a marked degree? It had typically not presented
this way.''

The medications the man had received initially, Leis said, could have
killed him. The stroke drug could have caused a hemorrhage, and the
medicine initially given to treat his misdiagnosed case of
Guillain-Barre had the potential to result in a stroke. That's why the
Mississippi and Georgia researchers became so determined to share
their findings on the link between polio and West Nile.

Leis has now seen four cases of West Nile-related polio, one
additional since he wrote his journal article. In Atlanta, Glass
received a call from a suburban physician one Saturday night in July.
That doctor was confounded by the symptoms of a patient he was seeing.
She had muscle weakness, along with fever and meningitis. The kind of
muscle fatigue she was experiencing was consistent with
Guillain-Barre, but that disease does not typically produce fever and
meningitis.

''The guy called me and said, `Help. I don't know what I'm looking
at,''' Glass said. ''And I said, `I don't know what you're looking at
either.'''

The 50-year-old woman, who lives in Louisiana, which was hard hit by
West Nile and was in Georgia visiting grandchildren, was transferred
to the university hospital in Atlanta. There, a neurology resident,
Dr. William Hewitt, examined her and confirmed the presence of an
unusual constellation of symptoms.

Glass spent the night poring over old medical textbooks and
epidemiology reports on the New York cases. All evidence began
pointing toward polio.

The woman treated by Glass is expected to survive but remains in a
rehabilitation hospital. The four patients in Mississippi also will
live, their doctor said, although three will probably have permanent
disabilities.

This story ran on page A1 of the Boston Globe on 9/24/2002.

? Copyright 2002 Globe Newspaper Company.