Eventually, officials from the public health department and the Centers for Disease Control traced the virus' origin. The Four Corners was the first place in the country where scientists learned that hantavirus was causing a deadly illness. In spring 1993, the virus killed 14 people, most of whom lived on or near the Navajo Nation.
The disease has since claimed victims each year. The New Mexico Department of Health announced Friday that a 45-year-old McKinley County woman has laboratory-confirmed hantavirus pulmonary syndrome. It is the first case of hantavirus in New Mexico this year. The woman has been hospitalized at University of New Mexico Hospital in Albuquerque and is listed in satisfactory condition, according to a news release from the department of health.
Hantavirus continues to appear sporadically in the U.S. More than half of all cases reported in the U.S. originate in the Four Corners, and New Mexico has more confirmed hantavirus cases than any other state.
The virus is spread by breathing in dust particles from the urine and droppings of rodents that carry the virus. In San Juan County, deer mice are the most common carriers, said Penny Hill, the infection control manager at San Juan Regional Medical Center.
Early symptoms of the virus include fever, muscle aches, chills, headaches, nausea, diarrhea, vomiting, abdominal pain and cough.
The symptoms progress to respiratory distress. Symptoms develop one to six weeks after exposure to a rodent with the disease.
The virus is fatal about 35 percent of the time, according to the Centers for Disease Control.
Nationally, since 1993, the CDC reports that there have been 617 confirmed cases of hantavirus in 34 states. New Mexico has had the most cases with 92, followed by Colorado with 79 and Arizona with 65.
Last year, New Mexico had one case of hantavirus, which was fatal. In 2011, the state saw five cases, including three that were fatal.
Since 1975, there have been eight cases in San Juan County, according to the New Mexico Department of Health.
The epidemic that struck fear into the region in 1993 started when a physically fit Navajo man suffering from shortness of breath was rushed to a Indian Health Service hospital and died quickly. Doctors learned the man's fiancee had died a few days early after suffering from the same symptoms.
Doctors tracked down other similar cases and found a pattern of young, otherwise healthy, Navajos who died from respiratory failure.
The Navajo Nation "got so much negative attention. I think back at how heart-wrenching it must have been for them," said Wren Propp, a former Daily Times staff writer who covered the epidemic for The Daily Times in 1993.
As doctors tried to uncover the mystery behind the unexplained deaths in May of that year, the Nation suffered from a damaging stigma.
Navajo traditions and herbs used in ceremonies were scrutinized as possible vectors for the mystery disease. Trips to Navajo schools by their pen pals from across the country were canceled because of fear. Chapter houses banned all media from meetings because journalists from across the country converged in the Four Corners to cover the deaths.
"They really were in a spotlight they never asked for and didn't deserve," Propp said.
Paul Ettestad, the state public health veterinarian, worked for the CDC in the spring of 1993. He traveled to the Four Corners and worked to learn more about the disease.
Ettestad said that after years of drought, there were heavy rains that spring, which increased vegetation and caused an increase in the deer mice population.
"We were able to show in houses where people got the disease, there were more rodents inside and near the houses," he said, adding that the people who fell ill had done activities like cleaning the house, which put them at a greater risk for hantavirus.
Once medical officials found a link between people with the disease and rodents, they were led to the Hantaan Virus, which is a similar virus that occurs in Asia and Europe.
In November 1993, medical personnel identified the specific hantavirus that occurred in the Four Corners and caused the outbreak. It was named Sin Nombre Virus, which means "virus without a name" in Spanish. The virus can cause hantavirus pulmonary syndrome.
Ettestad said the virus and disease had existed long before 1993, but it took that year's outbreak to recognize it.
To protect yourself:
• Avoid contact with mice and other rodents.
• Air out closed-up buildings before entering.
• Seal up homes and cabins so mice can’t enter.
• Trap mice until they are all gone.
• Clean up nests and droppings using a disinfectant.
• Put hay, wood and compost piles as far away as possible from your home.
• Get rid of trash and junk piles.
• Don’t leave your pet’s food and water where mice can get to it.
— New Mexico Department of Health
Ryan Boetel can be reached at email@example.com; 505-564-4644. Follow him on Twitter @rboetel