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MAN MADE
DISTASTER
• Man-made disaster are disasters in which the
principal direct causes are identifiable human
actions, deliberate or otherwise
• (Disaster Nursing and Emergency
Preparedness 2nd Ed. Page 4 by Veenema,
2007)
BIOLOGICAL
AGENTS
BIOLOGICAL AGENTS
• are pathogens used
deliberately to infect
persons as well as toxins
normally derived from
plants and animals.
(Disaster Nursing and Emergency
Preparedness 2nd Ed. Page 367 by
Veenema, 2007)
Category A – most deadly microbes known to man .They
are easily disseminated and are the highest priority.
1. Anthrax(Bacillus anthracis)
2. Botulinum toxin(Clostridium
botulinum)
3. Plague (Yersinia pestis)
4. Tularemia (Variola major)
5. Tularemia(Francisella
tularensis)
6. Hemorrhagic fever viruses
including Ebola, Marburg,
Lassa etc.
Category B – they share common characteristics
such as potential for moderate morbidity and lower
mortality. They are the second-highest priority
1. Brucellosis
2. Epsilon toxin or Clostridium perfringes
3. Salmonella, Shigella, E.coli etc.
4. Melioidosis and Psittacosis
5. Q fever and Typhoid fever
6. Ricin toxin(from castor beans)
7. Staphylococcal enterotoxin B
8. Viral encephalitis (from alphaviruseslike VEE,EEE,WEE)
9. Vibrio cholera and Cryptosporidium parvum
Category C – emerging agents that
is potential future infective threats such
as Nipah fever and Hantavirus
(Disaster Nursing and Emergency
Preparedness 2nd Ed. Page 404 by
Veenema, 2007)
BIOTERRORISM
Unlawful release of biologic
agent or toxins with the intent to
intimidate or coerce a
government or civilian population
(Disaster Nursing and Emergency
Preparedness 2nd Ed. Page 607 by Veenema,
2007)
ANTHRAX• zoonotic diseases generally found in
herbivores such as sheep, goat and
cattle that ingest spores from
contaminated soil. Causative agent is
a spore forming bacterium Bacillus
anthracis.
• -it can be spread through inhalation,
direct contact in the skin and
ingestion of the agent.
• -biosafety level 2 are recommended for
laboratory personnel who may come in contact
with anthrax specimen like laminar flow hood
with protective eyewear, gloves, and avoiding
activities that may produce aerosol or droplet
dispersal.
• -biosafety level 3 are recommended for
personnel who work extensively with anthrax
specimens including producing quantities for
research purposes. It is the same as biosafety
level 2 in addition of respiratory protective
equipment as needed, negative air pressure in
laboratory and decontamination of all waste
-health care workers who
come in contact with
anthrax patients should
use universal precautions
at all times including use
of rubber gloves, disposal
of sharps, and frequent
handwashing.
(Disaster Nursing and
Emergency Preparedness 2nd
Ed. Page 404-407 by Veenema,
2007)
Bioterrorism
in History
• The 2001 U.S. Anthrax Letter Attacks
– In this incident, letters containing
spores of the causative agent of
anthrax, Bacillus anthracis, were
sent to several U.S. media outlets
(print and TV) and to two U.S.
senators. A total of 5 letters were
sent, infecting 22 people, 11 with the
pulmonary form of the disease, and
11 with the cutaneous form. Five of
the victims with pulmonary anthrax
died.
• neuroparalytic, primarily foodborne illness. Caused
by anerobic bacteria Clostridium botulinum.
• -most common form is food borne botulism which
is through ingestion of infected honey and home
processed foods. Wound botulism involving
intravenous drug users who inject drugs
intravenously or subcutaneously
• -Coats, gloves, face shields and protective
cabinets are recommended for handling botulism
specimens. Laboratory personnel should be
vaccinated with C.botulinum anti-toxin. Universal
precautions should be used in caring for patients
suspected with botulism. Isolation is not necessary
but droplet precautions are instituted.
PLAGUE• -Plague is possibly the most feared
infectious disease in the history of human
kind. More than 200 million people have
died from plague.
• -It is caused by Yersinia pestis, a non motile
gram-negative bacterium. Transmission to
humans is typically through the bite of an
infected flea, although droplet spread from
patients with pneumonic plague is another
route of infection.
• -Biosafety level II precautions should be
used for specimens from patients suspected
of Y.pestis infection.
• -Biosafety Level III precautions are needed
only if extensive work with infected
specimens is expected.
• -Gowns, gloves, masks, and eye protection
should be worn for atleast the first 48 hours
of treatment.
PLAGUE IN HISTORY
• A secret branch of the Japanese army was
reported to have developed and dropped
Y.pestis – infected fleas and grain over
populated areas of China on several occasions
during World War II. The grain was used to
attract the rats causing outbreaks of plague.
Tulermia• -Tulermia,is a higly infectious zoonotic disease caused by the bacterium,
Franscisella tularenis.
• - It is typically found in animals such as rabbits and rodents, and can be
transmitted to humans in several ways. Contact with infected animal
carcasses; ingestion of contaminated meat, soil, or water; inhalation of the
bacterium especially in laboratory workers; Inoculation of the bacterium
via cuts or abrasions; as well as the bite of infected arthropods such as
ticks are among the ways tulermia can be contracted.
• -Tulermia is extremely infectious in aerosol form. Laboratory personnel
have inhalational tularemia simply byu examining an open culture palte.
• -Biosafety Level II precautions should be used for initial evaluation then
specimens should be forwarded to a BLS-3 laboratory for further testing
• -Universal precautions are recommended for patients suspected of
tularemia infection.
(Tener,et.al, Disaster Nuring and Emmergency Preparedness for Chemical, Biological,
and raidiological Terrorism and other hazards, 2007,page412-413,2nd edition)
Small pox• -Small pox, a DNA virus, is a member of the
genus othopovirus, like monkeypox, vaccinia, or
cow pox.
• -It contains a large complex viral genome and is
the only orthopox virus to be readily transmitted
from person to person.
• -The main portal of entry is the respiratory tract.
Skin, conjunctival, and transplacental infection
are less common.
• -Laboratory diagnosis of small pox is essential
and specimens should be obtained by people
vaccinated against small pox.
• -Because of its high infectivity, pathogenicity and
ease of person-to-person transmission, Biosafety
level IV (BSL-4) containment procedures,
protective equipment and facilities are necessary
for evaluation of potential small pox samples.
These procedures include specially designed
laboratory spaced secured with air locks and
decontamination rooms.
• -Personnel working in these spaces must wear a one piece positive pressure suit equipped with HEPA-filterred life-support system.
• -Multiple redundant back-up systems and other safety guards are also in place with BSL-4 to prevent release of these extremely dangerous microbes. (Department of health Human Service 1999)
• -All patients in whom small pox is suspected should be placed in strict respiratory isolation in negative pressure rooms.
• -Contacts of patients should be vaccinated and placed under surveillance. Isolated in-home or non-hospital facilities are preferable, due to high risk of transmission of smallpox via aerosol within hospital environments
Viral Hemorrhagic
Fevers
• -Viral hemorrhagic fevers (VHF) are
group of febrile illness caused by RNA
viruses from several viral families. They
include the filoviruses (Ebola and
Marburg), the arena viruses (Lassa and
New World arenaviruses), and tha
flaviviruses (Yellow fever among others).
• -Aerosol transmission of certain VHF
viruses has been theorized and has been seen
in animal experiments.
• -BSL-4 precautions are necessary when
handling specimens from patients suspected of
VHF infection. Every effort should be made to
ensure that specimens from these patients are
secured and properly sealed for transportation
of laboratories with the capability for VHF
diagnosis.
-In their analysis of VHF as a biological weapon, the working
group for Civilian Biodefense makes specific management
recommendations for patients suspected of having VHF infection,
including • Strict hand washing
• Double gloving
• Impermeable gowns
• N-95 masks or powered air-purifying respirators and negative pressure
isolation rooms
• Leg and shoe coverings
• Face shields and googles
• Restricted access to patients room
• Environmental disinfection
• -All medical personnel which have had close contact with patients
suspected of VHF
• infection before the safeguards were instituted should be placed under
medical surveillance.
(Tener,et.al, Disaster Nuring and Emmergency Preparedness for Chemical, Biological, and
raidiological Terrorism and other hazards, 2007,page415-418,2nd edition)
HISTORICAL USES OF
BIOLOGICAL AGENTS
SMALL POX• 1763: First use in warfare:
British commander Geoffrey
Amherst spread smallpox to
Indians by giving them
infected blankets
SALMONELLA• The 1984 Rajneeshee
bioterror attack was the
food poisioning of
751 individuals in The
Dallas, Oregon, United
States, through the
deliberate contamination of
salad bars at ten local
restaurants with
salmonella.