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.