2nd Distribution, SAFETY--Preventing Hantavirus Disease          

To: "  WRD Safety, Reston, VA "<safety_wrd>,
        "  WRD Regional Safey Officers, Reston, VA "<rso_wrd>
cc: "William G Shope Jr., Chief, Br. of Oper. Support, Reston, VA "<wgshope>,
        "Melvin Lew, Hydrologist, Reston, VA "<mlew>,
        "Ronald V James, Research Chemist, Menlo Park, CA "<rvjames>,
        "Carole Nethaway, Secretary (OA), Reston, VA "<ccnethaw>,
        "Alice C Dilandro, Secretary (S), Reston, VA "<dilandro>,
        "  WRD Archive File, Reston, VA "<wrd-archive>
From: "Catherine L Hill, ACH/Operations, Reston, VA "<clhill>
Subject: 2nd Distribution, SAFETY--Preventing Hantavirus Disease 
Date: Thu, 30 Oct 1997 18:06:11 -0500

NOTE:  At the present time, the most up-to-date distribution to all
       safety officers is safety_wrd@qvarsx.er.usgs.gov rather than
       the WRD distribution.so. 
   
Because the original WRD distribution.so on October 30, 1997, may not 
contain the most current list under this category, the following 
memorandum on Hantavirus prevention is being distributed a second time
to safety_wrd and rso_wrd.  
----------- 

In Reply Refer To:
Mail Stop 405

                              MEMORANDUM
                                                   October 28, 1997
 
To:       District Chiefs
          Chief, Branch of Regional Research - ER, CR, WR
          Chief, Hydrologic Instrumentation Facility
          Chief, National Water Quality Laboratory
          Chief, Yucca Mountain Project Branch
          Chief, Research Hydrologist, CVO

From:     Catherine L. Hill /signed, Stephen Blanchard, Acting/ 
          Assistant Chief Hydrologist for Operations

Subject:  SAFETY--Preventing Hantavirus Disease

This memorandum serves as a reminder of the severity of the 
highly-fatal hantavirus disease, provides current information from the 
Centers for Disease Control and Prevention (CDC), and includes a generic 
district safety plan for prevention of hantavirus infection. 

In May 1993, a new type of hantavirus was identified for the first time 
in the United States.  Rodents are the primary host for the virus that 
causes Hantavirus Pulmonary Syndrome (HPS).  As of September 13, 1996, 
HPS has been confirmed in 145 case patients from 25 States (Attachment 
1).  Telephone numbers of the CDC State contacts have been included in 
Attachment 1 to provide direct contacts for specific HPS information in 
every State.

The chances of getting the disease are very low, however, the 
consequences are very serious.  Infected people usually show symptoms 
similar to the flu:  high fever, muscle aches, chills, cough, and 
headache.  Major symptoms such as severe pneumonia and respiratory 
distress, and swollen lungs filled with fluid, may not appear until
the illness becomes life-threatening.  Once infected, timely medical 
treatment increases the chance of recovery.  The fatality rates so far 
are more than 50 percent, and there are no effective treatment methods
or vaccines available.

For Water Resources Division employees, the most probable exposure to 
the virus would be in disturbing rodent excreta or saliva in gaging 
stations.  A memorandum from the Branch of Operational Support dated 
March 17, 1994, ("SAFETY--Hantavirus Infection Prevention") presents 
CDC recommended guidelines to minimize possible contact with the virus.  
Districts should call their local CDC contacts (Attachment 1) to 
determine appropriate methods for working in areas with few or no 
documented cases.

In accordance with current CDC guidelines, eradicating all of the 
reservoirs of hantavirus hosts is neither feasible nor desirable.  The 
best available approach for disease control and prevention is risk 
reduction through environmental hygiene practices that deter rodents 
from colonizing in the work environment.  A generic district safety 
plan based on a July 1994 Utah District Plan and CDC guidelines for 
hantavirus infection prevention appears in Attachment 2.  This plan can 
be modified to meet local conditions, and should be followed in areas 
where infected rodents are endemic.

If you have any questions, please contact your regional safety officer.

2 Attachments

This memorandum is being distributed via email only.

cc distribution:  Regional Hydrologists:  NR, SR, CR, WR
                  Safety Officers
                  Regional Safety Officers
                  Chief Hydrologist
                  Assoc. Chief Hydrologist
                  ACH, Research
                  ACH, Technical Support
                  ACH, Operations
                  Chief, Br. Ops. Support
                  Chief, Off. Ground Water
                  Chief, Off. Surface Water
                  Chief, Off. Water Quality
                  Chief, NAWQA
                  Chief, DODECA
                  dilandro; mlfield; cpnelson; ccnethaw
                  wrd-archive


Attachment 1        Centers for Disease Control and Prevention
                         Hantavirus State Contacts and
                   Number of Hantavirus Pulmonary Syndrome Cases
 
State		Telephone No.	    No. Cases 1994-97	Total No. Cases

AK 		907-561-4406		 0			 0

AL 		205-260-3433		 0			 0

AR 		501-661-2817		 0			 0

AZ 		602-230-5808		 11			 22

CA 		510-540-2587 		 10			 15

CO 		303-692-2700		 5 			 11

CT 		203-566-4776		 0			 0

DC 		202-727-0557		 0 			 0

DE 		302-653-2870		 0			 0

FL	        904-922-8592 		 0			 1

GA 		404-657-2607 		 0			 0

HI 		808-586-4586 		 0			 0

IA 		319-335-4500		 1			 1

ID 		208-334-2235		 5			 10

IL 		217-782-2016		 1			 1

IN 		317-633-0263		 1			 1

KS 		913-296-5586		 4			 8

KY 		502-564-4478		 0			 0

LA 		504-568-4039		 0			 1

MD 		410-225-6162		 0			 0

ME 		207-287-1722		 0			 0

MA 		617-522-3700 x189	 0			 0

MI 		517-335-9629		 0			 0

MN 		612-623-5249		 1			 2

MO 		314-751-3334		 0			 0

MS 		601-960-7725		 0			 0

MT 		406-444-3986		 3			 5

NC 		919-733-7544		 0			 1

ND 		701-328-5262		 0			 5

NE 		402-471-2122		 0			 0

NH 		603-271-4657		 0			 0

NJ 		609-292-4030		 0			 0

NM 		505-841-2535		 8			 30

NV 		702-688-1335		 4			 7

NYC 		212-447-6220		 0			 0

NY 		518-486-3845		 1			 1

OH 		614-644-4659		 0			 0

OK 		405-271-4060		 1 			 1

OR 		503-229-5882		 4			 5

PA 		610-363-8500		 0			 0

RI 		401-274-1011		 1			 1

SC 		803-935-7061		 0			 0

SD 		605-773-4970		 2 			 5

TN 		615-262-6374		 0			 0

TX 		512-458-7676		 8			 9

UT 		801-538-6191		 5			 10

VA 		804-786-5142		 1			 1

VT 		802-863-7335		 0			 0

WA 		206-361-2914		 12			 13

WI 		608-262-0248		 1			 1

WV 		304-558-3530 x34	 0			 1

WY 		307-777-7431		 0			 1

                                         90                      169

Attachment 2        U.S. Geological Survey, Water Resources Division
                     District Hantavirus Infection Prevention Plan

1.  GENERAL INFORMATION

The first outbreak of Hantavirus infection occurred in the four corners 
geographical area where Arizona, New Mexico, Colorado, and Utah meet.  
The first known Hantavirus-related death was in May 1993.  Since then and 
up to September 13, 1996, the Centers for Disease Control and Prevention 
(CDC) had logged 145 case patients in 25 States.

The principal host and carrier of the virus is the common deer mouse, 
although other rodents also may be carriers.  Human infection can occur 
when infected saliva or excreta are introduced into the body through 
principal routes of exposure, including inhalation, ingestion, or 
introduction into the eyes or through broken skin.  A virus cannot 
survive without a host; however, it is uncertain how long the Hantavirus 
remains infectious once it is shed from an infected rodent.

The district currently operates a number of gage houses that have been 
determined to be infested with mice.  There are no certain treatments if 
contracted, and the current death rate, if contracted, is more than 50 
percent.  These conditions place personnel that routinely operate the 
gaging stations at risk for exposure to a virus that is best completely 
avoided.  Although it may be impossible to completely eliminate exposure 
to mice, the district is issuing this plan in an effort to reduce the 
threat of infection by minimizing exposure to mice in gage houses.  This 
plan outlines the procedures all district personnel should follow when 
disinfecting, cleaning, and sealing gage houses, which if infested, will 
be assumed infected.

Gage houses are to be cleaned by teams of at least two people.  Personnel 
should be medically able to engage in work activities described in this 
plan while wearing personal protective equipment.  Personnel assigned to 
disinfect and clean gage houses must have necessary medical examinations, 
including a blood screen for Hantavirus antibodies.  In addition to this 
plan, an orientation meeting will be held prior to its implementation to 
discuss the procedures outlined in the plan, to brief personnel about the 
hazards and the protection to be provided, and to address questions and 
concerns.  This plan shall become effective when approval and signature 
are made by the district chief.

2.  EQUIPMENT AND SUPPLIES

The following equipment and supplies are needed and should be obtained 
before gage houses can be effectively disinfected, cleaned, and sealed.  
In addition, it is recommended that all solutions and their containers be 
clearly labeled identifying their names, expiration dates, and directions 
for use.

   (1) Respirator protection, including half-face air-purifying
       respirators equipped with a filter/cartridge combination (HEPA
       filters (purple) and organic vapor/acid gas cartridges (yellow)),
       as outlined in a separate District Respiratory Protection Program.

   (2) Personal protective clothing

         A. Coveralls (disposable, water-resistant Tyvek).
         B. Boots (waterproof).
         C. Goggles.
         D. Gloves (disposable, waterproof).

   (3) Disinfectant (bleach) for use in sprayers, wash basins, and tubs
       (including measuring cups or other means of ensuring an effective
       ratio to prevent use of an unnecessary amount of bleach).

   (4) Sprayers (hand-pressurized and pumped, 1-3 gallon capacity) for
       saturating inside of gage houses and any waste that will be
       buried, and for rinsing and disinfecting boots.

   (5) Dust pans (or shovels) that can be disinfected easily for removing
       dead rodents, droppings, nests, or other waste that will be
       buried.

   (6) Water jugs (5 gallon size) filled with potable water for personal
       wash water for hands and face and for additional water for mixing
       bleach solutions.

   (7) Water jug spigot (at least one per work crew) for jug to be used
       as personal wash station.

   (8) Wash basins (Rubbermaid dishpan type or pails, two per work crew)
       for disinfecting gloves and for soaking coveralls and spent
       filters with bleach solution before disposing.

   (9) Mild dish soap or Liquinox for washing hands, face, respirator
       facepiece, and goggles.

  (10) Paper towels for wiping areas that cannot be sprayed and for
       drying hands and face.

  (11) Ziplock-type reclosable plastic bags (1 gallon size) for storage
       of filters and disposal of spent filters.

  (12) Garbage bags for disposal of gloves, coveralls, and spent filters
       (after soaking in bleach solution), and for disposing general
       trash that does not require burial.

  (13) Hardware for sealing houses (to be determined by technicians).

  (14) Decon or other mouse poison.

3.  KILLING THE VIRUS AND CLEANING THE GAGE HOUSE

   (1) Preparations

       A. Establish Zones

       The following zones should be established by using flagging,
       traffic cones, rocks, or other markers, to minimize transfer of
       potential contamination into clean areas such as vehicles and
       personal belongings, and to facilitate the work efforts.

         a. The Work Zone should include gage house, immediate
            surrounding area, and burial site.  The burial site should 
            be downwind from the gage house and removed enough from the
            river or stream that potential flooding will not be a
            concern.  Personal protective equipment should be worn at 
            all times in the Work Zone.

         b. THE WASH ZONE SHOULD ALWAYS BE LOCATED UPWIND FROM THE WORK
            ZONE.  If this is impossible (i.e., directly upwind would put 
            you in the middle of the river), remember that any location   
            is better than directly downwind.  The Wash Zone should
            provide a corridor for personnel to move from the Work Zone
            to the Clean Zone.  If you progressed from the Work Zone to
            the Clean Zone, the Wash Zone should include,

                 (i) Wash basin or pail with bleach solution,
                (ii) Space for removing personal protective equipment,
               (iii) Wash tub with bleach solution,
                (iv) Garbage bag,
                 (v) Clean garbage bag laid flat on ground, table, or
                     other surface for setting disinfected personal
                     protective equipment that will be reused,
                (vi) Water jug with spigot and accessible soap and paper
                     towels,
               (vii) Drinking water,
              (viii) Extras, such as potable water, more bleach, or
                     filters that you might need while working.

         c. The Clean Zone also should be located UPWIND from the Work
            and Wash Zones.  The Clean Zone should be removed enough
            that there is no chance that work activities will cross over 
            into areas designated as "clean," such as vehicles.

       B. Prepare A Burial Site

       All rodent refuse must be disposed by burying; never discard in 
       stream or as general trash.  A hole, 2-3 feet deep, should be   
       dug BEFORE personal protective equipment is donned.  (Note:
       Work in personal protective equipment will be heavy, hot, and   
       likely uncomfortable.  Taking the time to make needed
       preparation before personal protective equipment is donned will 
       greatly facilitate the cleaning process.)

       C. Dress For The Occasion

       Respiratory protection and personal protective clothing must be 
       worn while mice-infested gage houses are disinfected and
       cleaned.

         a. Respiratory Protection

            Respiratory protection needed for the protection of
            Hantavirus infection includes air-purifying respirators
            equipped with HEPA filters (purple).  A combination of
            HEPA filters with organic vapor/acid gas cartridges
            (yellow) will provide respiratory protection from chlorine 
            gas, which is liberated from bleach, and must be used
            while disinfecting and cleaning gage houses.

            Respiratory protection operating procedures are outlined
            in the District Respiratory Protection Program and should
            be followed.  For instance, it is easier to do negative
            and positive test fits first and then adjust the facepiece 
            to have a comfortable but sealed fit.  Adjusting the 
            respirator is easier before having gloves on.  Filters
            should be replaced any time during the cleaning effort
            when breathing becomes difficult or when chemicals such as 
            disinfectants can be smelled.  Spent filters should be
            disposed in plastic bags only after they have been soaked
            in bleach solution (discussed below).

         b. Personal Protective Clothing

            Personal protective clothing including coveralls, boots,
            goggles, hoods, gloves, and others, must be used during
            implementation of this plan.  Coverall legs should be worn 
            over the outside of the boots if possible.  Only a small
            part of the boots will be exposed by wearing the coverall 
            leg over the boot requiring minimal disinfection.  Hoods
            on coveralls should be worn at least until gage house is
            saturated with bleach solution and obvious mice refuse
            removed.

       D. Prepare Disinfectant

       CDC has determined that the Hantavirus is easily killed by
       saturating contaminated areas with common household
       disinfectants.  A solution of 2 cups of bleach to 1 gallon of
       water (1:8) is recommended in the March 17, 1994, WRD  
       Memorandum and is to be the disinfectant used by the district.  
       This bleach solution will be used in the wash zone discussed
       above to disinfect personal protective equipment and in
       sprayers to disinfect gage houses by saturating dead mice,
       excreta, nests, etc.

       Diluted bleach deteriorates more rapidly than concentrated
       bleach, and, therefore, may not be as an effective a
       disinfectant (D.W. Stephens, U.S. Geological Survey, written
       commun.,1995).  Solutions should be mixed at the beginning of
       each day and discarded at the end of each day.  Solutions
       should be replenished during the day when they get low and
       should be replaced if used to soak filters or coveralls.

       Never store diluted bleach in anything other than a tightly
       capped bottle (as opposed to a spray bottle), and never reuse
       the previous day's bleach solution that was used for washing
       personal protective equipment.  NEVER MIX ANOTHER DISINFECTANT
       SPECIFICALLY AMMONIA, WITH BLEACH!  THIS MIXTURE WILL RESULT IN 
       THE LIBERATION OF TOXIC GASES!

   (2) Disinfecting And Cleaning

       Disinfect any obvious areas of mouse habitation first.  Saturate 
       dead rodents, excreta, nests, and any other obvious remnants 
       thoroughly.  Carefully remove any waste from gage house and 
       deposit in hole for burial.  Continue to saturate waste material 
       in hole if needed.  When all refuse has been deposited in the 
       hole, refill the hole with the dirt that was removed.  Continue 
       disinfecting the gage house, by saturating all surfaces with 
       bleach solution using the sprayer, if possible otherwise, wipe 
       surfaces with paper towels dampened with bleach solution. 
       Ventilate gage house before reentering to seal, to ensure that 
       the chlorine gas liberated from the bleach has sufficiently
       dissipated.

   (3) Stopping Work

       It should always be assumed that the clothes and protective 
       equipment you are wearing while disinfecting and cleaning the 
       gage houses are contaminated.  Care should be taken when you stop 
       work, at any time for any reason, to appropriately disinfect 
       protective equipment to prevent transfer of potential 
       contamination to clean areas and personal clothing.  NEVER REMOVE 
       YOUR RESPIRATOR IN A POTENTIALLY CONTAMINATED AREA; ALWAYS 
       LEAVE THE WORK ZONE FIRST.  Remember the routes of exposure.
       Stopping for a drink of water without disinfecting your gloves   
       makes the risk for ingesting contaminants high.  Only under      
       emergency conditions should protective equipment be removed 
       before disinfecting.

         A. Leaving The Work Zone

            The following steps should be followed when you leave the 
            Work Zone for any reason, even if it is only for a short  
            period of time, such as getting a drink of water.

            ALWAYS EXIT THE WORK ZONE THROUGH THE WASH ZONE

              a. Disinfect gloves by dipping hands in dishpan with
                 bleach solution

              b. Remove coveralls and place in washtub with bleach
                 solution

              c. Disinfect gloves, as above

              d. Spray boots with bleach solution

              e. Remove goggles and wipe off EXTERIOR with paper towels
                 dampened with bleach solution

              f. Disinfect gloves, as above

              g. Remove respirator and wipe off EXTERIOR with paper
                 towels dampened with bleach solution, being very
                 careful not to introduce any water into the filters
                 (covers, however, should be wiped)

              h. Disinfect gloves, as above

              i. Remove gloves, and wash hands and face

         B. Day's End Or Completion Of Job

            The steps outlined below should also be followed at the      
            day's end or upon completion of a job.

              a. Spray and wipe off any equipment that is used in the 
                 cleaning process, such as sprayers, with bleach
                 solution, BEFORE removing any personal protective
                 equipment.

              b. Break down wash line, disposing of bleach solution
                 along exterior perimeter of gage house.

              c. Clean goggles and respirator facepiece thoroughly with
                 soap and water.  Follow the guidelines in the District
                 Respiratory Protection Program, or in the
                 manufacturer's instruction manual for cleaning the 
                 respirator.  This could be done at the work site or at
                 a more convenient place such as your home or motel
                 room.  Waiting until the next morning is not advisable
                 as it may not be completely dry by the time you need to
                 wear it.

   (4) Associated Hazards

         A. Hantavirus Infection

            If infected, symptoms typically develop within 2 to 4 
            weeks after exposure, although it may take up to 6
            weeks.  Early symptoms are similar to the flu and
            include high fever, muscle aches, chills, cough, and
            headache.  As the disease progresses, the victim
            experiences severe pneumonia (hantavirus pulmonary
            syndrome) and respiratory distress.  The lungs may swell
            and fill with fluid.

            If personnel involved in disinfecting and cleaning gage 
            houses develop any of these symptoms described, at any   
            time during or after the job, immediate medical 
            attention should be sought and appropriate USGS
            personnel notified.

         B. Bleach

            The dangerous part of common household bleach (Ca(ClO)2) 
            is the chlorine (Cl2) that is liberated as a gas when    
            bleach is exposed to air.  The Handbook of Toxic and     
            Hazardous Chemicals and Carcinogens (Sittig, 1985)      
            describes chlorine (Cl2) as "a greenish-yellow gas with
            a pungent odor.  It is the most common of the four 
            halogens which are among the most chemically reactive of 
            all the elements.  Chlorine reacts with body moisture to 
            form acids.  It is itself extremely irritating to skin,
            eyes, and mucous membranes."  The greatest risk of
            exposure to chlorine gas is through inhalation and eye
            and skin contact.

            The concentration recommended by WRD of 2 cups of bleach 
            to 1 gallon of water is a fairly concentrated solution.  
            The solution should be used with care.  The              
            filter/cartridge combination (HEPA/organic vapors/acid  
            gases (purple/yellow)) that will be issued for use 
            with the half-face, air-purifying respirator facepiece 
            will provide the respiratory protection needed for any
            liberation of chlorine gas while using the bleach        
            solution.  Contact with skin and eyes should not be a 
            problem if personal protective clothing is worn.  It is 
            important to keep these hazards in mind, particularly 
            when personal protective equipment is not being worn, 
            for example when the wash line is disassembled.

            First aid for accidental contact should be administered 
            and includes the following:

              a. Inhalation - Immediately move victim to fresh air.
                 Administer artificial respiration, if needed.  Seek
                 immediate medical attention.

              b. Eye or skin contact - Irrigate eyes or skin with
                 copious amounts of water.  Seek immediate medical
                 attention.

         C. Dehydration, heat exhaustion, heat stroke, and other
            physical hazards

            Personal protective equipment can be hot and cumbersome
            to work in.  Personnel should be alert and aware of
            associated hazards such as, dehydration, heat
            exhaustion, and heat stroke, particularly when working
            during hot days.  Although it may be time consuming and 
            somewhat of a bother, personnel should make sure they   
            pace themselves and take breaks as frequently as
            necessary.  Personnel should be aware of other physical 
            hazards inherent to the work environment, which may     
            include cuts and snake and insect bites.

4.  SEALING THE GAGE HOUSE

Gage house and immediate surrounding area should be sufficiently 
disinfected, cleaned, and aired BEFORE sealing begins, such that sealing 
the gage house can progress without use of personal protective equipment. 
Procedure for sealing gage houses should be determined individually by 
technicians that operate them.  Decon or other mouse poison should be 
placed inside cleaned and sealed gage houses.  Use of mouse poison may 
become routine if it is determined to be a fairly effective deterrent, at 
least for nesting.

5.  REVISITING THE SITES AND ONGOING EFFORTS

If there is any evidence of mouse infestation when sites are 
subsequently visited, interim guidelines described in the March 17, 1994, 
WRD Memorandum will be followed until the gage house can be revisited, 
disinfected, and cleaned according to the guidelines described in this 
plan.  Gage houses should be disinfected and cleaned, with additional 
attempts made to reseal the house, within a reasonable length of time.

6.  REFERENCES

   (1) "Handbook of Toxic and Hazardous Chemical and Carcinogens," 
       (2d ed.), p.217, by Sittig and Marshall, Park Ridge, N.J., 
       Noyes Publications, 1985.

   (2) Water Resources Division Operations Memorandum No. 94.01, 
       "SAFETY - Hantavirus Infection Prevention," March 17, 1994.

   (3) "Hantavirus Infection Prevention," U.S. Geological Survey,
       Water Resources Division. Utah District, July 27, 1994.