Nasty Infectious Diseases You Want To Avoid - Hantavirus
This is a respiratory illness caused by a relatively new strain of Hantavirus (a group of viruses carried by rodents) that causes its victims to gasp for air as their lungs fill with fluid. It kills about half the people it infects, usually within a week. The syndrome was first diagnosed in this country in 1993 at a Navajo reservation in the Four Corners area of New Mexico, Colorado, Utah, and Arizona.
Hantaviruses can be found throughout the world, where more than 170 names have been given to the hantavirus infections, including the often-fatal hemorrhagic fever. Until 1993, hantaviruses had been linked to the development of hemorrhagic fever. But the strain that was discovered in Four Corners caused a new disease, with debilitating flulike symptoms and respiratory failure.
Today, the number of infections with the hantavirus in the United States is rising and almost half have been fatal, according to the Centers for Disease Control and Prevention. Since the Navajo outbreak, more than 100 cases of hantavirus pulmonary syndrome have been reported in 21 states (including New York), with more than half of them fatal. In addition, cases have been diagnosed in Canada and in Brazil.
Cause - HPS is caused by a hantavirus first named Muerto Canyon (Valley of Death) virus for the spot on a New Mexico Navajo reservation where it was isolated. Because this name offended the Navajo, the virus was renamed sin nombre (or "no name") virus. The disease can be spread by several common rodent species (deer mice, white-footed mice, and cotton rats) and has been found in 23 states; it is most common in New Mexico, Arizona, and in California. Doctors believe victims become infected by breathing in the dried urine or feces of infected deer mice; about 30 percent of the deer mice in the Four Corners area carry the Sin Nombre agent. Infected rodents have been found in other parts of the country as well. Oddly enough, some victims have contracted the illness after little or no contact with rodents. Studies have also shown that the virus does not trigger infection in everyone it infects. In fact, the CDC acknowledges that the link between rodents and victims is unclear. Scientists don't know why some people become infected and others don't. Even more worrying, some people have exhibited symptoms of hantavirus pulmonary syndrome but don't have the virus. In fact, there were half a dozen incidents in California where young and healthy people died suddenly of acute respiratory failure, yet did not test positive for hantavirus or any other microbe. Some scientists believe the U.S. outbreak was triggered by climate irregularities associated with the El Nino (the occasional warming of waters in the tropical Pacific). While it is believed that the mice who carry the virus were probably infected for years, the climate-induced explosion in the deer mouse population may have fueled the spread of the disease in humans. In addition to contact with contaminated urine or droppings, people can become infected with the virus after being bitten by rodents. Many people who have developed the disease live in mice-infested homes. The hantavirus does not appear to be highly infectious, and it is almost always found in isolated cases.
Symptoms - Hantavirus pulmonary syndrome begins as a flulike illness with fever and chills, muscle aches, and cough; it can be easily misdiagnosed as hepatitis or an inflamed pancreas. The virus goes on to damage the kidneys and lungs, causing an accumulation of fluid that can drown the victim. The disease is fatal in almost half of all cases.
Treatment - There is no treatment approved specifically for hantavirus, but researchers are studying the effectiveness of the antiviral drug Virazole (ribavirin) for HPS.
Prevention - The CDC cautions homeowners to be cautious around rodent excretion, even though hantavirus is a rare disease. People should assume that all rodent excretions are infected, and should handle the droppings only after spraying them with disinfectant and wearing gloves.