Hantavirus six years later: ‘People don’t need to get this disease’

Monday, May 31, 1999 | 3:46 a.m.

Medical investigators scoured northwestern New Mexico and northeastern Arizona, taking blood samples, asking endless questions and collecting fleas from pets. In laboratories across the country, detectives looked for clues: Was it poison? bacteria? a virus?

Tourists canceled visits. State officials fretted. The cases kept coming.

Before long, evidence pointed to a new type of virus spread by rodents. Within a matter of weeks, the common deer mouse - named for its big eyes - was identified as the main culprit. Hantavirus became a household word.

Since then, more than 200 cases of hantavirus pulmonary syndrome have been confirmed in 30 states, some of them old cases, solved after the 1993 outbreak.

It is largely a disease of the rural West, although there have been a sprinkling of cases in the East, some caused by the deer mouse's cousins.

And it remains deadly. Nearly 45 percent of cases are fatal. Four people have died in New Mexico this year and one in Colorado.

"It's still a really difficult, complicated disease," said Paul Ettestad, hantavirus epidemiologist with the New Mexico Department of Health.

No one knows that better than Dan Bradshaw of Durango, Colo. He contracted the disease in 1996 after sweeping out a mouse-infested building at an electronic tower site he owned and then spending the night there.

Bradshaw says it took months - and visits to four different doctors - to get a correct diagnosis of the coughing fits, blackouts and other symptoms that were making him miserable.

A former bicycle racer and marathon runner, his athletic activities have been severely curtailed. "They hope that the lungs regenerate and repair themselves, but they're not quite sure they will," said the 50-year-old Durango resident, who owns a paging company with offices in Farmington and nearby Durango.

His message to others: "I should have recognized that was a dangerous situation, and come back with the proper equipment to clean it up. People don't need to get this disease."

Early on, hantavirus resembles the flu: fever and muscle aches, and sometimes chills, headaches, nausea and vomiting. That makes it extremely tough to diagnose on a first visit to a doctor.

And once the more serious symptoms start - acute respiratory problems and fluid buildup in the lungs - they generally progress very rapidly.

A 15-year-old New Mexico girl who died in April had been playing sports just hours before she became gravely ill, said Dr. Brian Hjelle, associate professor in the Department of Pathology at the University of New Mexico School of Medicine.

After the flurry of 1993 cases - 18 in New Mexico, 10 in Arizona and five in Colorado - the number of new cases dropped to a handful each year.

But a cluster this spring in New Mexico has Hjelle and others worried.

By Hjelle's count, there have been more than two dozen cases since the beginning of 1998 in the Four Corners states of New Mexico, Arizona, Utah and Colorado. That is more than twice as many as in the previous three years combined.

"The conventional wisdom is, it's El Nino," he said. The cyclically recurring disruption in the tropical Pacific made for a wetter-than-usual 1997-98, followed by a milder, drier "La Nina" winter just past.

More rainfall creates greater cover, more shelter and a bigger food supply - nuts, seeds, vegetation and insects - for rodents. That likely means more deer mice, more transmission of hantavirus among them and more encounters with humans.

The two winters preceding the 1993 outbreak also were marked by El Nino conditions.

Dwayne Howell, who owns a pest control company in the Durango-Farmington area, says he's noticed more mice. "We've had a tremendous amount of rodent calls since the fall of '97 - and last year it never stopped," he said.

Howell, who got interested in hantavirus because he knew two Durango-area victims who died, helped organize a recent public meeting on the disease in Farmington and was disappointed with the low turnout.

"I think sometimes people take a nonchalant attitude unless it's somebody they know, or somebody local, that's affected," he said. When that happens, "it starts hitting home, and you think, 'This is something serious."'

Because many of the 1993 cases were on the Navajo reservation, hantavirus at first was unfairly labeled by some as disease that struck primarily Indians - a misperception Howell says some people still have.

According to the Centers for Disease Control and Prevention in Atlanta, 75 percent of hantavirus cases in the United States occurred in whites; American Indians accounted for 22 percent.

On the 17 million-acre Navajo reservation, which stretches into New Mexico, Arizona and Utah, tribal and federal health agencies work together on hantavirus prevention.

Health educators are taking the message this spring to schools, tribal chapter houses, community events and special meetings: keep mice out of homes and outbuildings.

"Sometimes you can't afford to buy the materials from a store, so you can use ends of coffee cans and nail them over holes. We try to make it practical," said Ralph Fulgham, director of the division of environmental health services with the Navajo Area Indian Health Service in Window Rock, Ariz.

Fulgham thinks the message has gotten out. "We expected last year a great big outbreak of hantavirus, and I think one reason it didn't occur is that people are aware, and took precautions," he said.

In a recent telephone survey in four Colorado counties by the Department of Public Health and Environment, everyone had heard of hantavirus and most knew its symptoms.

"But there were still a number of people that said dry sweeping or dry vacuuming was an acceptable cleanup method - and that's not good," said state epidemiologist John Pape.

Hantavirus is typically caught by breathing dust contaminated with a rodent's infected urine, feces or saliva. Experts recommend a wet clean-up, using a disinfectant solution.

archive