Special Report: Non-Routine Crime Scene Pathogens
The following medical problems are identified as potential biohazards
at law enforcement crime scene investigations. Non-routine pathogens are
not intended to include "expected" human source bloodborne pathogens
(e.g., AIDS and hepatitis viruses). The list was compiled by staff at the
California Criminalistics Institute (CCI) and forensic scientists participating
in Supervising Criminalist Fred Tulleners Crime Scene III course on November
29, 1993. The sole purpose of this information is to increase the awareness
of all crime scene investigators to potential occupational medical problems.
This information is not provided as medical advice. Whenever an investigator
has concerns about health symptoms, they should seek and obtain professional
medical advice.
The following summaries include information regarding the etiologic
(disease causing) agents, vehicle of transmission, symptoms, treatment
and prognosis. The primary sources for medical information come from Current
Medical Diagnosis & Treatment, Ed. S.A. Schroeder, M.A. Krupp, et al.,
1990, Appleton & Lange; Encyclopedia of Medicine, AMA, Ed. C.B. Clayman,
1989, Random House; and, Harrison's Principles of Internal Medicine, Ed.
Eugene Braunwald, Kurt J. Isselbacher, et al., 11th edition, 1987, McGraw-Hill
Book Company.
ANAPHYLACTIC SHOCK
A life threatening
allergic reaction that may occur to people with extreme sensitivity to
a particular allergen (e.g., insect sting, injected pharmaceutical drug
or ingestion of a particular food or drug). The reaction occurs most often
following direct injection into the bloodstream provoking a massive release
of histamine and other chemicals. Blood vessels dilate with a sudden loss
of blood pressure (symptoms include itchy rash, breathing difficulty, swollen
tongue or throat). Severe reaction or collapse requires medical attention.
First aid includes raising the legs above the head to improve blood flow
to heart and brain and CPR as appropriate. Individuals who have suffered
severe reactions may be prescribed and carry preloaded epinephrine syringes
for injection.
CREUTZFELDT-JAKOB DISEASE (CJD)
A degenerative viral brain disease causing progressive dementia and myoclunus
(sudden muscular contractions). The disease is considered very rare, and
there is no effective treatment with death expected within weeks to months
after onset of symptoms (80% die within one year of diagnosis). CJD is
limited to adults with the average age of 60 at death. The etiologic agent
has been described as proteinaceous (prions) producing unconventional slow
infection. In 1968, the disease was shown to be infectious by allowing
chimps to eat organs from infected animals. While the source of CJD is
unknown, it has been found in monkey, other primates, sheep, goats, deer,
calves, minks, ferrets, cats, raccoons, skunks, mice, and rabbits. The
search for risk factors have focused on eating habits. Human-human transmission
has occurred by contaminated cranial electrodes, use of growth hormone
from infected cadavers and cornea transplants. The risk of occupational
exposure is considered low however reported cases include one neurosurgeon,
one pathologist and three pathology technicians. CJD prions are extremely
hardy and resist routine hospital sterilization, disinfection, and cleaning
procedures posing a serious challenge to Infection Control Professionals.
Formaldahyde fixed tissue is still infectious. Safe Work Practices in excess
of standard universal precautions are recommended with known or suspected
cases (Appendix A).
Class Discussion - A medical examiner serving the Riverside
area reportedly died from this disease (February 1992 Neurology
42 463). No other colleagues, law enforcement, or laboratory support personnel
are known to be infected. Reportedly, this experienced medical examiner
did not always follow standard Biosafety Level 2 (BSL 2) practices that
we are familiar with for personal protective equipment and hygiene in clinical
laboratory operations and which has now been integrated into Cal/OSHA standards
(October 1994, American Journal of Infection Control, 22, 5, p312-8).
HANTAAN VIRUS DISEASE
(at least 4 different viral agents) - Found in rodent urine, feces, and saliva in
high titer - 2 of the 4 agents were known in the USA but not known to cause
disease (until the Southwestern variety called Pulmonary Syndrome Hantavirus
- see below). High fever, backache, abdominal pain with some possible hemorrhagic
manifestations, polyuria (excessive urine production), recovery in 3 weeks
or kidney failure. Prognosis:
Mortality: Soviet 3-32%, China 7-15%, Korea 6.6%
Pulmonary Syndrome Hantavirus: 62%, [42 cases, 26 deaths, (Science
Vol. 262, 5 November 1993, p. 832.)]
Pulmonary Syndrome Hantavirus symptoms - Ordinary flu-like aches and
pains developing into respiratory distress within three days (capillaries
begin leaking); patients enter a critical phase over a period of hours
where it is harder and harder to breathe. Death may result from the loss
of blood (hemorrhaging) even with mechanical ventilation. Workers in a
known area of contamination who develop fever or respiratory problems within
45 days from exposure should immediately seek medical attention and inform
their physician of the potential of occupational risk of hantavirus infection.
The following information comes from "Hantavirus Infection - Southwestern
United States: Interim Recommendations for Risk Reduction" (MMWR
July 30, 1993, Vol. 42 / No. RR-11):
Rodents are the primary reservoir host of recognized hanta viruses although
other small mammals can be infected. While the deer mouse is the primary
reservoir in the southwestern United States, serologic evidence of infection
has also been found in pinion and brush mice, as well as western chipmunks.
Human infection may occur directly from aerosols from the animals because
"persons visiting laboratories where infected rodents were housed
have been infected only after a few minutes of exposure to animal holding
areas. Transmission may occur when dried material contaminated with excreta
are disturbed, directly introduced into broken skin, introduced onto the
conjunctivae, or, possibly, ingested in contaminated food or water. Persons
have also become infected after being bitten by rodents."
Person-to-person transmission has not been associated with transmission
of previously identified hantavirus including the southwestern US variety.
Arthropod vectors (fleas, ticks, mites, insects) are not known to transmit
the disease. Dogs and cats are not known to be host reservoirs.
Respiratory protection with at least a High Efficiency Particulate Air
(HEPA) filter respirator is a special precaution for workers (clean-up)
in homes of persons with confirmed Hantavirus infection or buildings with
heavy rodent infestations, and also for persons in affected areas who frequently
handle or are exposed to rodents (e.g., mammalogist or pest control workers).
"Insufficient information is available at this time to allow general
recommendations regarding risks or precautions for persons in the affected
areas who work in occupations with unpredictable or incidental contact
with rodents or their habitations. Examples of such occupations include
telephone installers, maintenance workers, plumbers, electricians, and
certain construction workers. Workers in these jobs may have to enter various
buildings, crawl spaces, or other sites that may be rodent infested. Recommendations
for such circumstances must be made on a case-by-case basis after the specific
working environment has been assessed and state or local health departments
have been consulted."
Class Discussion - It was suggested that the recommendation
to consult with local health departments apply to other diseases (e.g.,
TB) before entering a suspicious crime scene. One participant pointed out
that they had declined to enter a crime scene involving the death of an
infant that had been feverish for a few days before death - no trauma or
blood was noted. Investigators were referred to poison control and public
health. The family subsequently developed meningitis and required hospitalization.
A coroner fell ill for 10 days, but did not require hospitalization.
LYME DISEASE
Caused by a bacterium/spirochete
in rodents that is transferred to humans by tick bites. In the California
Northern Coast, wood rats (not deer mice) and a non human-biting tick maintain
the disease agent. Transfer to humans in California is by the Western black-legged
tick that does not efficiently maintain the disease agent. Symptoms include
skin changes (red dot gradually expanding), flulike symptoms and joint
inflammation. Treatment with antibiotics is more effective during early
stages of disease progression that may include the heart and nervous system.
Class Discussion - It was suggested to use insect repellents
to help avoid tick bites. One participant had clinical laboratory experience
attempting to culture and identify the etiologic (disease causing) agent.
Reportedly, the best way to identify this disease is by recognition of
the reddish circular, growing "target" pattern around the tick
bite. (In early 1994, the media reported that a reliable blood test had
been developed.) While chemical repellent has some success, the most effective
prevention is covering exposed skin.
MENINGITIS
Swelling of the membranes
(meninges) that cover the brain and spinal cord. The disease is caused
by a variety of microorganisms. Viral meningitis is usually not serious
and affects up to 12,000 people each year. Meningococcal meningitis is
the most common bacterial meningitis affecting up to 5,000 young people
(70% under age 5) each year. The meningococcal form is life-threatening
and needs prompt medical treatment. Symptoms include fever, severe headache,
nausea and vomiting, dislike of light, and a stiff neck. Symptoms may develop
rapidly over a few hours. A blotchy skin rash develops in about one-half
of the cases. In severe cases, confusion, delirium, seizures, and coma
and shock occur. Although up to 40% of the population are nasopharyngeal
carriers, very few develop the disease, which is transmitted by droplets.
Patients receiving prompt medical treatment usually recover. Where close
household contact (or mouth-to-mouth resuscitation) occurs, prophylactic
antimicrobials can be effective. Pneumococcal meningitis is the most common
cause of meningitis in adults and second most common cause in children
over the age of six.
PLAGUE
(Black death of the 14th
century killing 25 million) - Today, spring and summer rodent flea bites
cause 10-50 cases per year with the risk of death less than 5% with prompt
treatment with antibiotics. A vaccination is available for individuals
at high risk. The public health concern is that wild rats will pass the
fleas to urban rodents infecting people when the rat dies and the fleas
leave the carcass. Symptoms of bubonic plague - within 2 - 5 days, fever,
shivering and severe headache; followed by "buboes" - smooth
oval, reddened, intensely painful swellings usually in the groin and less
common in armpits and neck or elsewhere. Bleeding around the buboes leading
to dark patches may occur with occasional blood poisoning. Untreated, the
disease is 50% fatal. Pneumonic plague may result as a complication of
bubonic plague causing severe coughing producing blood, frothy sputum and
labored breathing which is nearly always fatal unless diagnosed and treated
early. The pneumonic plague can pass from person to person by infected
droplets expelled during coughing.
POISON OAK
Grows as vines or bushes
and leaves have three leaflets. The harmful oil resin, called urushiol,
is also found in poison Ivy and Sumac. Touching results in itching, burning,
and blistering at the site of contact. The response is not immediate and
may occur 24 to 48 hours after contact. People with sensitivity may have
extremely severe skin reactions. Prompt first aid (within 5 minutes of
contact) by washing the affected area with soap and water may avoid rash;
sponging with alcohol is an alternative. After the rash develops, application
of calamine lotion may help relieve itching and act as a drying agent.
Corticosteroids may be recommended in severe cases (either topically for
small areas - or by mouth if a large area is affected). Neither scratching
or the watery liquid from the blisters spread the rash.
Class Discussion - One participant indicated that a crime scene
investigator in the Los Angles area had lost several fingers to a severe
skin reaction, and that highly sensitive persons may develop symptoms without
direct contact with plant material. It was recommended that Laboratory
Directors maintain a list of highly sensitive staff and make field assignments
as appropriate to avoid the risk of exposure to highly sensitive personnel.
It was pointed out that alcohol did not work in one case to denature the
poison oak contamination.
PULMONARY TUBERCULOSIS
Caused
by Mycobacterium tuberculosis and transmitted from person to person via
the aerial route (other routes have been documented but none of major importance).
Tubercle bacilli form nuclei for water droplets in respiratory secretions
and are expelled during coughing, sneezing, and vocalizing. The moisture
evaporates leaving the desiccated bacilli airborne for long periods. Settled
bacilli can absorb moisture from the environment and remain viable for
weeks. Settled bacilli can be thrown back into air currents by walking
through the room. While the number of bacilli excreted is usually not large
and household contact for many months is required for disease transmission,
some infectious persons may be highly contagious because of the extent
of disease (in the respiratory system) which relates to an increased concentration
of expelled bacilli and frequency of coughing. Mycobacteria are susceptible
to ultraviolet light and disease transmission rarely occurs out-of-doors
in daylight. Increased fresh ventilation is the most important environmental
measure to prevent disease transmission.
Initial infection is from 1 to 3 organisms that reach the deep lungs
(alveoli) where they are ingested by scavenger cells in the blood (macrophages)
and transported to regional lymph nodes where they are destroyed or pass
to the blood stream resulting in widespread dissemination. Surviving bacilli
inside the macrophages continue to multiply for 2 to 8 weeks until the
cellular immune response (T-lymphocytes) is effective in stopping the spread
of disease by grouping the infection into nodules (granulomas). Mycobacteria
may survive inside the granulomas but be held in check from further spread,
and the granulomas may calcify and be detectable on chest X-rays. This
stage of infection usually does not produce symptoms and is termed primary
tuberculosis. The overwhelming majority (90%) of primary tuberculosis cases
(in the US) end at this stage. (95% of the individuals who successfully
resolve the primary infection undergo complete healing with no subsequent
recurrence.) Progressive primary tuberculosis occurs in the remaining 10%
of the infected cases resulting in the following symptoms: a dry cough
at first progresses to a productive cough containing sputum, pus and sometimes
blood. Other symptoms include fatigue, weight loss, anorexia, low-grade
fever, and night sweats. Untreated, the pulmonary lesions grow and normal
pulmonary architecture is lost, resulting in death in about 60% of the
cases with a median course to death of 2.5 years. Sometimes the disease
reactivates. Reactivation tuberculosis presents similar symptoms as pulmonary
tuberculosis and occurs when the immune system is no longer effective in
containing the "walled-off" bacilli.
In 1989, the Encyclopedia of Medicine reported that "Almost all
properly treated patients with tuberculosis are cured. . . . The only cause
of treatment failure is noncompliance." In December 1992, a government
hearing was convened regarding the returning epidemic of tuberculosis in
New York City. Dr. Karen Brudney testified about increased resistance to
the two mainstay drugs against TB (i.e., isoniazid and rifampin). Approximately
1 in 3 were resistant to isoniazid in New York relative to 1 in 10 nationally.
Approximately 1 in 5 were resistant to both first-line drugs which reduced
the cure rate from 100% to less than 50%. Additionally, the treatment time
goes from 6 months to 18 to 24 months with many months of injections. The
second-line drugs that then must be used are more toxic and less effective.
In December 1993, the media reported that Roosevelt Island sanitarium was
again opened up in New York to ensure treatment regimens are followed.
Prevention of TB after some types of exposures may be medically indicated
with drugs. A number of live TB vaccines are available and known collectively
as BCG. However, the efficacy (ability to produce the desired effect) is
in question. Controlled studies in North America and Britain indicate that
vaccination offered greater than 80% protection while little or no protection
developed in other populations. The vaccine is not routinely used in laboratory
personnel. BSL 2 precautions are recommended for preparing acid fast smears
while BSL 3 precautions are recommended for propagation and manipulation
of cultures or handling non-human primates (because they have a respiratory
reflex like humans and can transmit the disease through the aerial mode).
BSL 3 add respirators to the list of potential personal protective equipment,
and the 1988 version of "Biosafety in Microbiological and Biomedical
Laboratories" has a special precaution for the use of "Molded
surgical masks or respirators are worn in rooms containing infected animals."
An article in Occupational Health & Safety, by Neville Tompkins, Vol.
62, May 1993, reports that while some experts disagree, NIOSH recommended
in October 1992, that high-powered air purifying respirators be worn by
health care workers. Reportedly, other major public health and medical
organizations including the CDC, American Lung Association, and Infectious
Disease Society of America recommend (in part) that "Health care workers
and others entering TB isolation rooms should wear particulate respirators
which resemble surgical masks but are far more effective in blocking TB
bacteria." In October 1993, the CDC recommended filter characteristics
capable of removing particles of 1 micron size at 95% efficiency. The only
filters that meet that standard today are HEPA filters that remove particles
of 0.3 micron size at 99.97% efficiency. In May 1994, NIOSH proposed changes
in the respirator certification process to test filters for particles of
0.3 microns but at three different efficiencies (99.97%, 99%, and 95%).
RABIES
An acute viral disease
caused by the transmission of infected secretions, usually saliva, from
an infected dog licking over damaged skin, mucous membrane, or from a bite.
Transmission is also known from infected aerosols and postexposure prophylaxis
is always indicated subsequent to a bite where the bat cannot be sacrificed
for brain tissue testing (other common reservoirs include skunks, foxes,
and raccoons). The virus replicates in muscle tissue near the point of
entry and then travels from the wound along nerve pathways to the brain
where further replication occurs in the gray matter. The virus then spreads
to other tissues and organs via autonomic nerves. Depending on the amount
of virus introduced, the host's immune defenses, and the distance the virus
must travel to the brain, incubation varies significantly from 10 days
to over 1 year (average 4 to 8 weeks). Clinical symptoms include fever,
headache, malaise, myalgias (muscular pain), anorexia, nausea, vomiting,
sore throat, inability to drink water - progressing to marked increase
of motor activity, excitation, confusion, hallucinations, combativeness,
bizarre aberrations of thought, shorter periods of lucid thought - progressing
further to coma and finally death by respiratory failure. Once symptoms
start, the disease is almost always fatal with only three well documented
cases of recovery. Post exposure prophylaxis is effective. Follow-up evaluation
from over 575 cases of bites from confirmed rabid animals has shown that
no person who has received both passive (antirabies antiserum) and active
immunization (antirabies vaccine) has developed the disease. In the USA,
fewer than 5 rabies cases are reported each year.
ROCKY MOUNTAIN SPOTTED FEVER
Caused
by a parasitic microorganism (a type of rickettsia) to arthropods (insect
and insect-like animals, e.g., lice, fleas, ticks and mites). Like viruses,
rickettsiae can only procreate by invading the cells of another life form.
Transfer to humans is by the bite of an infected tick or their feces where
the rickettsiae can pass through a break in the skin to access blood. About
1,000 cases are reported per year and mostly on the Atlantic seaboard.
Symptoms include anorexia, nausea, and sore throat progressing to fever,
aching, and headache in 3 to 10 days. Two to six days after symptoms begin,
small pink spots appear on the wrists and ankles, then spread over the
body, darken, enlarge and bleed. Treatment with antibiotics usually cures
the disease. Untreated cases marked with high fever may result in death
from pneumonia or heart failure. Prevention: use insect repellent in tick-infested
areas, examine the body daily, and gently pull away ticks with forceps
when found.
SAN JOAQUIN VALLEY FEVER
Caused
by inhalation of a mold that grows in soil - about 60% of infections are
subclinical (unrecognized except for a positive coccidioidin skin test).
Symptoms may be more severe in other cases requiring medical attention.
Fewer that 1% of the cases result in spreading of the disease from the
chest or meningeal form which have significant long-term mortality rates.
Prognosis in cases where the disease is limited to the chest is good by
providing necessary symptomatic therapy. Limited disease symptoms after
10-30 day incubation include influenza-like illness with malaise (vague
feeling of illness or depression), fever, backache, headache, and cough.
Scabies - Mites barely visible as a white dots burrow into the skin where
they lays eggs and can be seen on the skin as tiny, gray, scaly swellings,
usually between fingers, on wrists and genitals and armpits. Infestation
causes intense itching, especially at night, and scratching results in
scabs and sores. Although infestation is most likely through physical contact
(e.g., sexual intercourse), scabies is highly contagious and can pass from
one person to another who is standing close beside the person infested.
Usually the whole family is treated by applying an insecticide lotion to
all skin below the head.
SNAKE BITE
May be predominantly
neurotoxic (coral snake) causing respiratory paralysis; or predominantly
cytolytic (e.g., rattlesnake) causing local pain, redness, swelling, and
forcing the flow of blood out of surrounding tissue. Tingling in the mouth,
metallic taste, nausea and vomiting may occur. Emergency treatment includes:
immobilizing the patient and part bitten in a horizontal position. Avoid
manipulation of the area bitten and immediately transport the patient to
a medical facility for treatment. Do not give the victim alcohol, stimulants,
or apply ice. The trauma to underlying tissue resulting from incision and
suction performed by untrained personnel is probably not justified considering
less than 10% of the venom can be recovered.
SPIDER BITE
Most spider toxin
causes only local pain, redness, and swelling and is self limiting. The
more venomous black widow causes generalized muscular pains, muscle spasms
starting at the site and spreading, and rigidity. Symptoms may continue
for several days. Death from cardiac arrest or respiratory failure occur
occasionally in children and the elderly, but are uncommon in adults. Treatment
for black widow bites is to relieve symptoms with narcotics or muscle relaxants.
Antivenom is usually not required but is used for the very young or elderly
who do not respond to the above treatment. There is no proven treatment
for the bite of the brown recluse spider. Its bite may lead to the death
of local tissue, requiring excision; other treatments are being developed.
TETANUS
Caused by spores of a
bacteria found in soil and manure (and human intestines); 100 cases per
year, producing pain and tingling at the site of inoculation followed by
spastic reaction of nearby muscles. Usually stiffness of the jaw ("lockjaw")
and neck, dysphagia (difficult to swallow), and irritability. Spasms and
rigidity of muscles develop in the abdomen, neck and back. Asphyxia (unconsciousness
or death caused by lack of oxygen) may result from spasms in the larynx
or chest. Spasms usually subside in 10 to 14 days. The disease is completely
preventable by active immunization beginning with childhood vaccination
and obtaining booster doses every 10 years or at the time of puncture injury
(including human bites) if it occurs 5 years after a dose.
Non-Routine Crime Scene Pathogens
APPENDIX A
Biological Safety Level 2 (BSL 2) standard and special safe working
practices were intended for controlled facility/healthcare environments
and address a variety of subjects such as facility design, access, hazard
warning signs, containment devices (such as ventilation hoods), vector
control, specialized equipment, housekeeping and waste handling. Crime
scene environments do not present laboratory controlled conditions, making
the use of personal protective equipment and basic hygiene potentially
more important to avoid exposure incidents.
1. No mouth pipetting (also ref. Cal/OSHA standard CCRT8 5193 (d)(2)(L)).
Mechanical pipetting is used.
2. No eating, drinking, smoking, or applying cosmetics in the work area
(ref. 5193 (d)(2)(I)).
3. Procedures are performed carefully to minimize aerosols (Cal/OSHA
requires procedures be performed in a manner to minimize splashing, spraying,
spattering, and generation of droplets - ref. 5193 (d)(2)(K)).
4. Use standard barrier protections whenever physical contact with contaminated
items is anticipated (ref. 5193 (d)(3)(I) for gloves; (K) for body clothing;
and (L) for caps and shoe covers). Standard barrier protections include:
a. Plastic or rubber (water proof) gloves; b. Lab coats or jump suits.
5. Use appropriate personal protective equipment (or containment equipment)
whenever: a) procedures have a high potential for creating aerosols, or
b) high concentration or large volumes of infectious agents are used: a.
Particulate surgical mask and goggles or a face shield (this is specifically
recommended for evidence technicians scraping blood for laboratory analysis
- ref. MMWR June 23, 1998, Vol. 38 No. S-6, page 24). b. Cal/OSHA requires
the equipment listed in a. (above) whenever splashes, spray, spatter, or
droplets of blood or other potentially infectious materials may be generated
and eye, nose, or mouth contamination can be reasonably anticipated - ref.
5193 (d)(3)(J).
6. Barrier protection is removed before leaving the laboratory (Cal/OSHA
requires hand washing after the removal of gloves or other personal protective
equipment - ref. CCRT8 5193 (d)(2)(E)).
7. Sinks are required for hand washing and hands are washed before leaving
the laboratory (Cal/OSHA requires employers to provide antiseptic hand
cleanser in conjunction with clean cloth/paper towels or antiseptic towelettes
when hand washing facilities are not feasible; employees are then required
to wash their hands with soap and running water as soon as feasible - ref.
CCRT8 5193(d)(2)(D)).
by Tom Valentine, Safety Coordinator,
California Department of Justice
Bureau of Forensic Services,
California Criminalistics Institute
June 1995 Update
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