Navajo Area Is Sifted for Clues to Fatal Disease

Nearly 50 medical investigators scattered across the Navajo Reservation on Sunday searching for clues to explain the outbreak of a mysterious respiratory disease that so far has claimed 10 lives.

In a medical puzzler recalling the first appearance of legionnaire’s disease in 1976, scientists cannot explain why young, healthy people are falling prey to adult respiratory distress syndrome, an often-fatal condition in which lung tissue swells to the point where the body is starved of oxygen.

A 13-year-old Navajo girl became the youngest victim when she died from the illness Saturday only hours after collapsing at a graduation party. The oldest victim was 31.

A total of 25 people have fallen ill in northwestern New Mexico and northeastern Arizona since March, state and federal health officials said at a news conference. Among the 15 survivors, six have recovered, while the remainder are still hospitalized, some in critical condition.

Laboratory tests so far have not found a likely virus, bacterium or toxin.

“I think we would classify this as an epidemic at this point because it’s more cases of acute respiratory distress syndrome than we would expect to be seen, especially in a small area,” said deputy state epidemiologist Ron Voorhees.

Investigators are reportedly looking at the possibility of a toxin or infectious substance but have come up with nothing. They say the illness may be contagious, but not highly contagious since most family members and others who were in contact with victims have not developed it.

Meanwhile, investigators have been notified by California health officials that three, possibly four, people under 30 died of unexplained respiratory distress this winter in Northern California.

Three of the deaths were in Humboldt County, but California health officials said that one appears to have been caused by a reaction to an X-ray procedure at a hospital. The fourth case was in San Francisco.

At this point, said California state epidemiologist Dr. George Rutherford, there is no evidence to connect the California deaths to those at the reservation, but it is “prudent policy,” he added, to investigate thoroughly.

“We feel obligated for the sake of the New Mexico folks to try to run these to ground,” Rutherford said.

He agreed that given the existing clues in the New Mexico cases, the cause may indeed be a toxin. If an influenza strain were the culprit, Rutherford said, those afflicted would most likely be infants and people over 65 years of age. In talking to New Mexico officials, Rutherford said, he has learned that several of the cases appeared in young, otherwise healthy, people who were in exceptionally good athletic shape.

The current outbreak has afflicted 18 Navajos, five Anglos, one Hopi and one Latino, health officials said. All lived on or near the 24,000-square-mile Navajo reservation, the nation’s largest.

The disease in most cases starts off with flu-like symptoms, including fever, muscle aches and cough, then abruptly worsens. Patients have jammed Indian Health Service hospitals and clinics throughout the Four Corners region, according to IHS doctor James Cheek, who said the agency is checking for similar cases over the past two years.

Doctors have placed respiratory distress patients on ventilators and administered a host of antibiotics, hoping that one might prove effective. The sickest victims are at the University of New Mexico Hospital, where the critical care unit has been closed to all other patients for the time being.

Dr. Jay Butler of the Centers for Disease Control and Prevention in Atlanta said the CDC has provided sophisticated laboratory support in the investigation. And three CDC staffers arrived in New Mexico over the weekend to help identify the illness.

Since legionnaire’s disease erupted in the 1970s, scientists have new cell cultures and a procedure called the polymerase chain reaction, which analyzes a microbe’s DNA to determine what genus or species it belongs to.

“The bad news is, with the example of legionnaire’s disease, it took four months before that agent was identified,” Butler said.

Times staff writer Michele Fuetsch contributed to this story from Los Angeles.