SAFETY--Managing Safety and Health Hazards When Working in and around Streamgaging Stations: A Lesson Learned from an incident in the Iowa District
In Reply Refer To: November 23, 1994
Mail Stop 405
WATER RESOURCES DIVISION MEMORANDUM NO. 95.06
Subject: SAFETY--Managing Safety and Health Hazards When Working
in and around Streamgaging Stations: A Lesson Learned
from an incident in the Iowa District
This memorandum reports on an incident in which four Iowa Distric
employees were infected with Histoplasmosis caused by contact with
dust produced during the renovation of a streamgaging station in
August 1994. An account of the incident appears in attachment 1.
Attachment 2 provides information on Histoplasmosis as well as measures
to protect workers from infective organisms.
There are many other safety and health hazards associated with the
operation and renovation of streamgaging stations. The prime examples
include potentially fatal Hantavirus infections from the dust associated
with mice droppings and saliva in the gagehouses, and Lyme Disease caused
by the bite of infected deer ticks, and bees or hornets. Other hazards
include poisonous snake bites; Leptospirosis from direct contact with
an infected animal's urine or tissue, or from indirect contact with
contaminated water or soil; and Rat-Bite Fever caused by the bites of
wild rats or mice.
All data-collection installations should be maintained on a regular basis
and be inspected annually to identify and correct any safety and health
hazards. Regular inspections of these structures can identify and eliminate
openings or holes where bats, birds, or rats can live. Prior to working in
and around streamgaging stations, it is the responsibility of the supervisors
that all potential hazards associated with the job be identified using job
hazard analysis (JHA), and that proper personal protective equipment (PPE)
be provided to employees. It is our hope that by taking proper precautions,
most accidents at streamgaging stations can be prevented.
If you have any questions about this memorandum, please contact G. J. Hwang,
the Division Safety Officer, at (703) 648-5255 or send EDOC to "GJHWANG."
Catherine L.Hill
Acting Assistant Chief Hydrologist
for Operations
2 Attachments
This memorandum does not supersede any previous WRD memorandum.
Distribution: A, B, S, FO, PO
Attachment 1
HISTOPLASMOSIS INCIDENT
Iowa District
In August 1994, 4 of a 6-member working crew from the Iowa District
were infected with Histoplasmosis while renovating the streamgaging
station located on the North River near Norwalk, Warren County, Iowa.
Histoplasmosis is caused by the direct contact or inhalation of dust
from bat manure, and primarily affects the lungs. It is believed that
the organisms grew in the holes of the broken concrete blocks in the
upper part of the gagehouse, were enriched by bat or bird droppings,
and became airborne in large plumes of dust when concrete blocks were
broken by the 4 employees who became ill. Because of the long incubation
period of Histoplasmosis, symptoms of the disease were detected from
August 30 through October 30.
CHRONOLOGY OF ILLNESS:
August 30, 1994 -- One employee became ill with symptoms including
headache, body aches, fever, chills, heavy sweating, and chest
congestion.
September 1-25, 1994 -- Other members of the construction
crew began to exhibit some of the same symptoms. Blood samples were
taken from the 6 employees who worked at the site and tested positive
to the Histoplasmosis fungus for the 4 directly involved in the demolition
of the concrete block gagehouse. Although one employee tested "negative"
to the Histoplasmosis fungus, he was diagnosed with a pneumonia-type illness
involving his right lung. Of the 4 employees tested positive, only one
required medication and time away from work. For the other 3 employees who
tested positive, lingering effects of the illness were minimal with slight
chest congestion.
October 30, 1994 -- One of the 3 employees who was mildly affected by the
fungal infection initially has since needed medical attention and
hospitalization for inflammation of the chest/lung area. Also, one of the
contractors who was at the site before any demolition was done worked on
disconnecting, removing, and securing the electric service from the gagehouse
and has developed the same physical symptoms.
Attachment 2
Managing Health Hazards
Associated With
Bird and Bat Excrement
(Excerpt from United States Army Environmental Hygiene Agency,
Aberdeen Proving Ground, Maryland 21010)
HISTOPLASMOSIS:
1. What is histoplasmosis?
Histoplasmosis is an infection caused by the fungus Histoplasma
capsulatum. The symptoms vary greatly but it primarily affects
the lungs. Occasionally it invades other parts of the body;
this form of the disease is called disseminated.
2. Who gets histoplasmosis?
Anyone can get histoplasmosis. Positive histoplasmin skin
tests are seen in as many as 80 percent of those living in
endemic areas such as the eastern and central United States,
although the majority of those infected do not have symptoms.
The chronic pulmonary form is more common in males and the acute
disseminated disease is more frequently seen in immunocompromised
individuals, such as persons with AIDS.
3. How is the fungus spread?
The organism grows in soil that has been enriched with bat or bird
droppings. Spores are produced that can become airborne in dust if
the soil is disturbed. Inhalation of these spores may cause
infection. The disease is not acquired through person-to-person
transmission.
4. What are the symptoms of histoplasmosis?
Symptoms vary from asymptomatic (for the majority of those infected)
to mild respiratory illness to chronic disseminated disease. The
acute benign respiratory disease is characterized by respiratory
symptoms, general malaise, fever, chest pains, and a dry or productive
cough. Distinct patterns are seen on x-rays. Chronic pulmonary disease
resembles chronic pulmonary tuberculosis and progresses over months or
years. The disseminated form can be seen as acute or chronic and is
usually fatal unless treated.
5. How soon after exposure do symptoms appear?
If symptoms appear, it is usually within 5 to 18 days after exposure,
with an average of 10 days.
6. Where is the fungus that causes histoplasmosis found?
Histoplasma capsulatum is found throughout the world and is endemic
in certain areas of the United States. These organisms grow in soil
around old chicken houses, in caves harboring bats, and around
starling and blackbird roosts. This fungus is also found in areas
inhabited by the common brown bat, in soils with high organic content,
and decaying trees.
7. What is the treatment for histoplasmosis?
Specific medications are used to treat severe cases of histoplasmosis.
Mild disease usually resolves without treatment. Past infection
results in increased resistance to infection.
8. What can be done to prevent the spread of histoplasmosis?
It is not practical to test or decontaminate all unconfirmed or
confirmed Histoplasma capsulatum sites, but the following steps
can be taken to minimize exposure: Avoid areas that may harbor
the fungus; Minimize exposure to dust by spraying with water o
oil before stirring up potentially contaminated sites; Restrict
work in high risk areas to persons with a positive histoplasmin
skin test. If persons with negative skin tests must enter the
area, they should wear disposable clothing and a self-contained
breathing apparatus (SCBA) or face mask capable of filtering out
particulate matter above 1 millimicron in diameter.
DECONTAMINATION:
Decontamination of droppings and associated soil for control of
Histoplasma capsulatum IS NOT RECOMMENDED because no safe and effective
material is available. Decontaminated soil is subject to reinfestation
as long as the nutrients that enabled the fungus to establish itself are
still available.
PROTECTION OF WORKERS FROM INFECTIVE ORGANISMS:
1. Preliminary Consultation: Prior to disturbing accumulated droppings,
inform the occupational medicine physician or the proposed activity
and consult with an industrial hygienist for advice on personal safety
measures such as protective clothing and the proper selection, use,
and fitting of respirators.
2. Breathing Protection: When working with accumulated droppings, wear
a NIOSH-approved full face respirator with high efficiency particulate
air (HEPA) filters capable of excluding particles of 0.3 micron size
or a supplied air respirator with full face piece. Dust and particle
masks will not provide adequate protection and are not approved for
this use.
3. Protective Clothing: Wear disposable coveralls, gloves, boots, and
hats to protect personal clothing from contamination with infective
organisms. Workers must not wear their own personal street clothing
under the disposable coveralls. Seal the glove/sleeve and boot/leg
interfaces with duct tape before entering the worksite. Before
leaving the site, vacuum the protective coveralls, boots, and glove
using a HEPA vacuum, then walk to an excrement free area, remove the
protective clothing, and place it in plastic bags prior to removing
respiratory protection. Treat disposable clothing believed to be
contaminated with disease agents as infectious waste.
a. Nondisposable work clothing and respirators should be removed, placed
in a plastic bag, and sealed. These items must be disinfected in the
bag before final cleaning and reuse.
b. If the disposable coveralls or other protective clothing are torn, the
workers must shower prior to putting on their street clothes. It is
recommended that workers shower and thoroughly wash their hair at the
end of their shift.
DISPOSAL:
1. Double bag the droppings and associated soil in 3 mil or thicker
plastic bags, close the bags securely, and transport them directly
to a landfill to be buried. If the droppings have been proven to
contain Histoplasma capsulatum and/or Cryptococcus neoformans, they
may be incinerated. Do not place the bags in a dumpster or leave at
a collection point for later pickup as they could be torn during
handling and release their potentially infectious contents. Wear
protective clothing and equipment when collecting the bird and bat
droppings for final disposal.
2. You may clean up small amounts of fresh droppings by scraping or
hosing with water.