Hantavirus warning accompanies spring

By Sun Advocate

In May 1993, an outbreak of an unexplained pulmonary illness occurred in the southwestern United States in the Four Corners area shared by Utah, Arizona, New Mexico and Colorado.
A young, physically fit Navajo man suffering from shortness of breath was rushed to a hospital in New Mexico and died very rapidly.
While reviewing the case, medical personnel discovered the victim’s fiancee had died a few days before after showing similar symptoms.
Local health agencies combed the Four Corners region to identify patients with similar case histories.
Within a few hours, the medical teams located five young, healthy individuals who had died after acute respiratory failure.
The U.S. Centers for Disease Control, in conjunction with tribal and public health agencies in the Four Corners region, promptly mounted an intensive investigation in the area.
During the next few weeks, as additional cases of the disease were reported in the Four Corners area, physicians and scientific experts worked intensively to narrow the list of possible causes.
The particular mixture of symptoms and clinical findings directed researchers away from possible causes such as bubonic plague or exposure to herbicides or influenza and toward a virus, indicated the U.S. Centers for Disease Control.
Due to ample vegetation and ground cover nurtured by heavy rainfall in spring 1993, the Four Corners region experienced a bumper crop of rodents.
Medical investigators and researchers trapped the known virus carriers in the area and conducted tissue studies on the rodents as well as the victims.
The virologists with the U.S. Centers for Disease Control utilized several laboratory testing procedures, including newly developed methods designed to pinpoint virus genes at the molecular level.
The laboratory results linked the pulmonary syndrome to an unknown type of hantavirus and positively identified the disease’s principal carrier – the deer mouse.
The CDC researchers subsequently determined that the hantavirus had actually been present – but unrecognized – for at least 34 years or as early as 1959.
Since the 1993 outbreak, hantavirus pulmonary syndrome incidents have been identified in more than half of the states across the nation. But HPS cases are still fairly uncommon occurrences and the chances of becoming infected with the disease are relatively low, pointed out the federal medical research and health agency.
Nevertheless, hantavirus represents a potentially deadly disease and obtaining immediate intensive medical care for infected individuals is essential once the symptoms appear.
Based on limited available research data, the federal agency indicates the initial symptoms of hantavirus develop between one and five weeks after exposure to infected rodents and droppings.
Early universal symptoms of the disease include fatigue, fever and muscle aches, especially in the thighs, hips, back and sometimes the shoulders.
Approximately half of the individuals infected with hantavirus experience headaches, dizziness, chills and/or abdominal problems like nausea, vomiting, diarrhea and pain.
Earache, sore throat and rash are extremely uncommon symptoms in hantavirus pulmonary syndrome cases.
Four to 10 days after the initial phase of the illness, the late symptoms of HPS appear.
The late symptoms of hantavirus include coughing and severe shortness of breath.
Once the final stage of hantavirus pulmonary syndrome starts, the disease progresses rapidly.
No specific medical treatments or cures for hantavirus pulmonary syndrome currently exist, explains the U.S. Centers for Disease Control.
But early intubation and administration of oxygen therapy appear to help HPS patients through the period of severe respiratory distress.
In the event a patient is experiencing full distress, the intensive care treatment is less likely to be effective, adds the federal medical research and health agency.
Castle Valley residents who come into contact with deer mice or rodent infested sites and develop fever, deep muscle aches and severe shortness of breath should consult a doctor immediately, emphasizes the federal medical research and public health agency.
Rodents shed the hantavirus in urine, droppings and saliva.
Transmission occurs when urine, droppings or nesting materials are disturbed and tiny droplets containing the virus get into the air through a process known as aerosolization.
Transmission can happen anywhere infected deer mice and rodents have infested, cautions the U.S. Centers for Disease Control.
Medical research studies indicate that common house mice do not carry hantavirus. However, carrier rodents can invade residential structures, outbuildings and cabins.
To alleviate the risks of contracting hantavirus, Castle Valley citizens should take steps to prevent rodents from infesting private residences and work places.
In addition, people who discover infestations should exercise several precautionary measures.
The relatively fragile HPS viruses are surrounded by a lipid or fatty envelope, according to the federal health agency and medical researchers.
The envelope can be destroyed and the virus killed by fat solvents like alcohol, ordinary disinfectants and household bleach.
When faced with handling infested sites, medical experts recommend that Castle Valley residents:
•Thoroughly ventilate all homes, cabins and enclosed outbuildings before tackling the chore of cleaning up rodent droppings or mice nesting sites.
•Put on latex rubber gloves before starting to clean a rodent infested area.
Refrain from stirring up dust by sweeping or vacuuming deer mice droppings, urine or nesting materials.
•Completely wet contaminated sites with household detergent or general purpose disinfectants to deactivate the virus.
A hypochlorite solution prepared by mixing one and one-half cups of household bleach in one gallon of water may be used in place of commercial disinfectants.
•Remove the rodent droppings and potentially contaminated nesting materials with a damp towel.
Mop or sponge down the area with general purpose disinfectants or the hypochlorite solution.
Spray dead the dead rodents and deer mice with the general purpose disinfectant or bleach and water solution.
Double-bag the carcasses and damp towel as well as all cleaning materials.
Bury, burn or discard the carcasses in an appropriate waste disposal system.
Disinfect the latex rubber gloves before removing from hands.
After removing the disinfected gloves, thoroughly wash hands with soap and warm water.
In order to reduce the potential for deer mouse infestations, the U.S. Centers for Disease Control recommends that residents:
•Keep homes clean, especially kitchens. Wash dishes, wipe off counters, mop floors and store food in covered containers. Keep tight-fitting lids on garbage cans and discard uneaten pet food at the end of the day.
•Set spring-loaded traps near baseboards.
Put U.S. Environmental Protection Agency approved rodenticide under plywood or plastic shelter along baseboards.
Follow product instructions carefully – rodenticides are poisonous to pets and people.
•Seal all entry holes into structures one-fourth inch wide or larger with lath metal, cement, wire screening or patching materials.
Use metal flashing around the base of wooden, earthen or adobe structures.
Install flashing 12 inches above and six inches below ground level.
•Clear brush, grass and junk from around foundations. Elevate haystacks, woodpiles and garbage cans.
Whenever possible, locate haystacks, woodpiles and garbage containers at least 100 feet away from homes or structures.
Eliminating all rodents and deer mice in the Castle Valley area is not feasible.
However, Carbon and Emery County residents can limit rodent and deer mice populations to low numbers by implementing the designated control practices, concludes the federal agency.