Hantavirus Pulmonary Syndrome (HPS) and the workplace

April, 2010

Topics covered

Description of Illness

Source of virus

How it’s Transmitted to People

Personal and Occupational Risk

Prevention and Control

DOSH Policies

What are the symptoms of Hantavirus Pulmonary Syndrome?

1. Begin 1 to 6 weeks after inhaling the virus

2. Symptoms are usually apparent within 2-6 days; “flu-like” illness including fever, sore muscles, headaches, nausea, vomiting, and fatigue.

3. Will cause shortness of breath due to fluid filled lungs as the disease gets worse. Hospital care is then required.

4. It is usually a serious infection and about 1 out of 3 people diagnosed with HPS have died.

Link to Washington Dept. of Health hantavirus fact sheet

Source of Hantavirus

Deer miceSmall, native rodents 5 to 8 inches long. Their fur resembles deer, dark on the back and white on the legs and underside. The tail is also dark on top and white underneath.

(Major reservoir in western US)

Cotton ratsBuild their nests out of cotton. They have small ears and dark coats. Found primarily in southern U.S.

Deer Mouse

Cotton Rat

The Hantavirus

Hantaviruses have been shown to be viable in the environment for 2 to 3 days at normal room temperature.

Affected by conditions of environment such as temperature, humidity, and whether indoors or outdoors.

Also affected by the rodent’s diet – affects the chemistry of the urine.

Ultraviolet rays in sunlight kill hantaviruses.

Transmission to People

Exposure by infected deer mice, cotton rat through inhalation of aerosolized virus excreted in:– Urine– Feces– Saliva

Exposure to hantavirus through:– contaminated dust after disturbing or cleaning rodent

droppings or nests,

– living or working in rodent-infested settings such as cabins, homes, barns, vehicles, outbuildings

– handling of wild rodents without protection

RISK - Who can get Hantavirus

Any man, woman or child who is around mice or rats that carry the harmful virus.

Person to person spread has not occurred in the United States.

Through 2009 there have been 41reported cases of HPS among residents of Washington State, 14 (36%) of which were fatal. Between one and five cases occur annually. Cases occur in both western and eastern parts of the state. The median age of cases in Washington State is 35 years (range 14–75 years). The death rate and median age of cases in Washington are similar to the national rates.

Click here Reported Cases in United States

Exposure Precautions

If you have been exposed to rodents or rodent infestations and have symptoms of:– fever,– deep muscle aches,– severe shortness of breath

See physician immediately and inform your

doctor of possible exposure to hantavirus from rodents.

Activities associated with cases of Hantavirus infection

Sweeping out a barn and other ranch buildings

Trapping and studying mice

Entering a barn infested with mice

Planting or harvesting field crops

Occupying previously vacant dwellings

Disturbing rodent-infested areas while hiking or camping

Living in dwellings with a sizable indoor rodent population

Using compressed air and dry sweeping to clean up wood waste in a sawmill

Handling grain contaminated with mouse droppings and urine

Some occupations may be at more risk than others:

Telephone installers, maintenance workers, plumbers, electricians, and certain construction workers.

Workers in these jobs might have to enter buildings, crawl spaces, or other sites that are potentially rodent-infested, and Hantavirus has been reported among these workers.

Occupational Risk

For workers that might be exposed to rodents as part of their normal job duties, employers are required to comply with relevant occupational health and safety regulations. Employers are required to develop and implement an exposure control plan to eliminate or reduce the risk and hazard of Hantavirus in their workplace.

DOSH Policies on Hantavirus

During a workplace inspection, compliance staff will be required to issue a citation if there is clear evidence of potential hantavirus exposure for employees by contaminated aerosols or materials as outlined in WRD 11.55

Click here to view WRD 11.55

To view the L & I Employer information Bulletin on HPS (2000), click here

Click here to view DOSH standard on pest control

Prevention – Rodent Control

Seal up building holes and gaps

Do continuous or frequent trapping

Clean up rodent food sources and nesting sites using appropriate gloves and respirator.

Eliminate debris in and around buildings and grounds.

Rodent control in and around the home, offices and work areas remains the primary strategy for preventing hantavirus infection.

Store food 12 to 15 inches off the floor and 12 to 18 inches away from the wall. Use rodent-proof containers when possible.

Screen dumpster drainage holes with hardware cloth

Don't leave pet food out overnight

Eliminate water sources available to rodents

Prevention – Rodent Control

Eliminate possible nesting sites – grass, woodpiles etc.

Employers need to evaluate and control employee exposure to hantavirus respiratory hazards by identifying and controlling the hazards. It is the responsibility of the employer to ensure workers are protected.

One method of avoiding employee exposure is to use proper respiratory protection where exposure could occur.

Respirator Rule- click here

Disease Prevention

Cleaning Use rubber, latex, vinyl or nitrile gloves.

Thoroughly wet contaminated areas with a bleach solution or household disinfectant (1 ½ cups bleach in 1 gallon water).

Swipe up contaminated materials with damp towel then mop or sponge the area with bleach solution or disinfectant.

Spray dead rodents with disinfectant then double-bag.

Bury, burn or throw out rodent in appropriate waste disposal system.

Disinfect gloves with disinfectant or soap and water before removing.

Thoroughly wash hands with warm water & soap.

Cleaning (continued)

DO NOT use a vacuum of any type including one equipped with HEPA filters for cleaning dried rodent droppings or other dry debris.

It blows air around and may create virus aerosols.

• What is known about this topic?Hantavirus pulmonary syndrome (HPS) is an uncommon but severe disease that can occur after contact with an infected rodent or rodent-infested area.

• What about children?Although reports of HPS are uncommon in children, they can experience severe morbidity and a clinical course similar to that of adults.

• What are the implications for public health practice?HPS should be considered in children and adults with unexplained acute respiratory distress, especially if rodent exposure is noted; preventive measures include rodent control in homes and workplaces, and play areas where children may be present.

Important to instruct children to avoid contact with rodents or areas of infestation.

In Conclusion

For more information about Hantavirus or rodent control, call your state or local health department.

Pam EdwardsDept. Labor & Industries – DOSH

360-902-6457edwp235@lni.wa.gov

Or see the CDC web page at: http://www.cdc.gov/ncidod/diseases/hanta/hps/index.htm

Or see the Washington State Department of Health at: http://www.doh.wa.gov/EHSPHL/factsheet/hanta.htm

L & I – DOSH Hantavirus factsheet

Adapted from PowerPoint developed by: Cindy Smith, PHR

City of Ellensburg, HR Director http://www.ci.ellensburg.wa.us/

 

Additional information from: Center for Disease Control & Prevention (CDC)