Microbes in biological warfare
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Transcript of Microbes in biological warfare
MICROBES IN
BIOLOGICAL WARFARE
M.BLESSED HEARTLEY
ST. JOSEPH’S COLLEGE, TRICHY.
INTRODUCING MICROBES• Micro-organisms (or microbes for short) play a very important role in
our lives. Some microbes cause disease but the majority are
completely harmless. In fact we couldn’t live without them, but they
could live without us.
• These microscopic organisms play a key role in maintaining life on earth, fixing gases and breaking down dead plant and animal matter into simpler substances that are used at the beginning of the food chain.
• Biotechnologists can also exploit the activities of microbes to benefit humans, such as in the production of medicines, enzymes and food. They are also used to breakdown sewage and other toxic wastes into safe matter.
WHAT ACTUALLY IS BW?
• BIOLOGICAL WARFARE (BW) also known
as GERM WARFARE is the use of biological
toxins or infectious agents such as bacteria, viruses,
and fungi with intent to kill or incapacitate humans,
animals or plants as an act of war.
BIOLOGICAL WEAPONS:-
• Consists of either living organisms that can reproduce, such as bacteria, or viruses, or toxic materials produced by living organisms, such as toxins or physiologically active proteins or peptides.
• Viruses – Venezuelan Equine Enchephalitis (Very Lethal)
• Bacteria – Bacillus anthracis (Anthrax)
• Toxins – Staphylococcal Enterotoxin and BotulinumToxin
DELIVERY METHODS
• Gas release and aerosol releases via airplanes,
submarines, bombs, artillery and missiles
• HCN missiles and central burster missiles
• Poisoned arrows
• Poisoned bullets
• Poisoned hand grenades
• Poisoned letters
• Food delivery: food, coffee, water, creams, juice
Why to use biological weapons instead of
nuclear weapons?
BECAUSE……..
• Effective and Cheap
- 1 gram of botulinus intoxication can kill 10
million people.
- Purified Botulism is 3 million times more
potent than our best chemical weapon.
- SCUD Missile filled with Bolulism Toxin
would affect an area 16 times best chemical
weapon.
• Cost Comparison
• To Affect 1 Square Kilometer of Area
- Conventional Weapons $2000
- Nuclear Weapons $ 800
- Chemical Weapons $ 600
- Biological Weapons $ 1
Biologics are the “Poor Man’s Atomic Bomb”
• Not Easily Detectable
• They cannot be detected by x-rays, dogs, and most
devices, making them easy to transport.
• Infected humans can serve as transport devices.
NAME OF SOME AGENTS:-
• Bacillus anthracis (Anthrax)
• Franciella tularensis (Tularemia)
• Variola major (Smallpox)
• Botulinum toxin (Botulism)
• Yersinia pestis (Plague)
• Viral Hemorrhagic Fevers
ANTHRAX
• Anthrax is an acute disease caused by the bacterium Bacillus anthracis. Most forms of the disease are lethal, and it affects both humans and other animals. There are effective vaccines against anthrax, and some forms of the disease respond well to antibiotic
• Bacillus anthracis is an infectious agent of the anthrax.
In humans, three types of anthrax infection occur:
Inhalational, cutaneous (skin), and gastrointestinal.
I. Inhalation anthrax
Inhalation anthrax follows inhalation of spore-
bearing particles. Surviving spores are taken up by
white cells in the lungs and transported to the lymph
nodes in the spaces around the heart, where
"germination" of the spores may occur up to 60 days
later. The reasons for variation in germination time are
not known.
II. Cutaneous anthrax
Cutaneous anthrax follows the deposition of the bacteria
or spores into the skin through cuts or abrasions or
insects. Areas of exposed skin such as arms, hands, face and
neck are the most frequently affected. After the spore
germinates in the skin tissue, toxin production results in
local swelling initially. Then small blisters appear and lead
to the development of black scabs that dry and fall off in
one to two weeks. Lymph nodes near the skin lesions can
swell and get painful. Antibiotics do not change the course
of the skin lesions, but they can prevent the disease from
getting beyond the skin. Without antibiotics, the mortality
rate has been reported to be as high as 20%; with
antibiotics, death due to cutaneous anthrax is rare
III. Gastrointestinal anthrax
Gastrointestinal anthrax occurs following
deposition and subsequent germination of spores
in the upper or lower gastrointestinal tract. The
former results in swelling and infection in the mouth
or esophagus. The latter results in intestinal
manifestation such as nausea, vomiting, bloody
diarrhea and abdominal pain. If the disease becomes
advanced, it can eventually resemble the end stages of
the inhalation type. The mortality from treated
intestinal anthrax is approximately 50%.
ANTHRAX LETTERS
• A letter containing anthrax was received by Tom Daschle, the leader of the United States Senate.
• 23 members of his staff and 5 police officers tested positive with nasal swabs.
• Citizens begin stockpiling Cipro.
• This is the letter that was sent to NBC anchor Tom Brokaw with cutaneous anthrax and that infected Brokaw's assistant, Erin O'Connor. The envelope is postmarked September 18 from Trenton, N.J. The handwriting is identical to the one sent to the New York Post below postmarked on the same date and sent from the same place.
TULAREMIA• Francisella tularensis, the organism that causes tularemia, is
one of the most infectious pathogenic bacteria known, requiring inoculation with or inhalation of as few as 10 organisms to cause disease.
• F. tularensis is a hardy non-spore-forming organism capable of surviving for weeks at low temperatures in water, moist soil, hay, straw or decaying animal carcasses.
• It is considered to be a dangerous potential biological weapon because of its extreme infectivity, ease of dissemination and substantial capacity to cause illness and death.
SYMPTOMS OF TULAREMIAThe bacteria’s point of entry determines the symptoms.
* Symptoms of ulceroglandular tularemia (infection through the skin) include:
• skin ulcer at the point of contact with the infected animal or at the site of a bite
• swollen lymph nodes near the skin ulcer (most often in the armpit or groin)
• headache
• fever
• chills
• fatigue
* Symptoms of glandular tularemia (infection through the
skin) are similar to ulceroglandular symptoms but without a
skin ulcer.
* Symptoms of pneumonic tularemia (the most deadly form
of this disease, which is transmitted through inhalation)
include:
• cough
• chest pain
• breathing difficulty
• high fever
• pneumonia (lung infection)
• muscle pain
* Symptoms of oculoglandular tularemia (infection through
the eye) may include:
• eye irritation
• eye pain
• eye swelling
• discharge and/or redness of the eye
• a sore on the inside of the eyelid
• swollen lymph glands behind the ear
* Symptoms of oropharyngeal tularemia (infection through
ingestion of the bacteria) include:
• sore throat
• ulcers in the mouth
• swollen lymph glands in the neck
• tonsillitis (swollen tonsils)
• Vomiting
• diarrhea
* Symptoms of the most rare form of this disease, typhoidal
tularemia, include:
• a very high fever
• extreme fatigue
• diarrhea
• Vomiting
Typhoidal tularemia can lead to pneumonia and an
enlarged liver and spleen.
TREATMENT FOR TULAREMIA
• Each case is treated according to its form and
severity. Early diagnosis allows for immediate
treatment with antibiotics.
• Surgical intervention may be required to drain
swollen lymph nodes or to cut away infected tissue
from a skin ulcer. You may also be given medications
for fever or headache symptoms.
SMALLPOX• The British considered using smallpox as a biological warfare agent
during the French and Indian Wars (1754–63), against France and its
Native American allies at the Siege of Fort Pitt.
• On one occasion in June 1763, two blankets and a handkerchief that
had been exposed to smallpox were given to representatives of the
besieging Delawares with the aim of spreading the disease and
ending the siege.
• During World War II, scientists from the United Kingdom, United
States and Japan were involved in research into producing a
biological weapon from smallpox.
• Plans of large scale production were never carried through as they
considered that the weapon would not be very effective due to the
wide-scale availability of a vaccine.
BOTULINUM TOXIN—BIOLOGICAL WEAPON
• Botulinum toxin is the most poisonous substance known to
man. Even a small amount is lethal. Bacteria in
the Clostridium genus produce it.
• As a weapon, the toxin might be released in the air or placed
in the food supply. The toxin causes the disease botulism.
CAUSES
• Botulinum toxin poses a great threat. It is easy to produce
and transport.
• Only one gram of the toxin evenly released and inhaled
could kill one million people. However, it is hard to keep
stable for release in the air.
• Botulinum toxin is colorless and odorless. The toxin cannot
be passed from one person to another.
SYMPTOMS
• Double or blurred vision
• Trouble swallowing
• Difficulty speaking
• Weakness in clenching jaw
• Droopy eyelids
• Loss of head control
• Weakness, on both sides, starting at the head and working
down the body
• Constipation
• Paralysis
TREATMENT• Early therapy with an antitoxin is essential to decrease
resulting nerve damage. Treatment should start before test
results are available.
* Antitoxin
If started early, an antitoxin can stop the paralysis from
progressing and may shorten symptoms. It does not
reverse the disease process.
METHODS TO ELIMINATE THE
TOXIN
* Methods to eliminate the toxin include:
• Enemas
• Suctioning of stomach contents
PLAGUE
• It is caused by the bacteria Yersinia pestis, which has been
the cause of three great human pandemics in the sixth, 14th,
and 20th centuries.
• Throughout history, the oriental rat flea has been largely
responsible for spreading bubonic plague.
• After the flea bites an infected animal, the organisms can
multiply inside the flea.
• When an infected flea attempts to bite again, it vomits
clotted blood and bacteria into the victim's bloodstream and
passes the infection on to the next victim, whether small
mammal (usually rodent) or human.
SIGNS AND SYMPTOMS SIGNS
AND SYMPTOMS• People infected with plague may suddenly develop high a
fever
• painful lymph nodes and
• Have bacteria in their blood.
• Plague is contagious, and when the victim coughs, plague can spread.
• Pneumonic plague is the most severe form of the disease and if untreated, most people die.
TREATMENT
• Victims of suspected plague will be isolated for the first
48 hours after treatment begins. If pneumonic plague is
present, isolation may last for four more days.
• Since 1948, streptomycin has been the treatment of
choice for plague but other antibiotics may be given.
• Without treatment, 60% of people with bubonic plague
die, and 100% with pneumonic and septicemic forms
die.
VIRAL HEMORRHAGIC FEVERS
• The hemorrhagic fever viruses (HFVs) are a diverse group
of organisms that are all capable of causing clinical disease
associated with fever and bleeding disorder, classically
referred to as viral hemorhagic fever (VHF).
• These organisms can be divided into 4 distinct families of
viruses.
• Filoviridae: Ebola and Marburg viruses;
• Arenaviridae: Lassa fever virus and a group of viruses
referred to as the New World arenaviruses (eg, Junin,
Machupo, Guanarito, and Sabia viruses);
• Bunyaviridae: Crimean Congo hemorrhagic fever virus,
Rift Valley fever virus, and a group of viruses known as the
"agents of hemorrhagic fever with renal syndrome" (eg,
Hantaan, Dobrava-Belgrade, Seoul, and Puumala viruses);
and
• Flaviviridae: dengue, yellow fever, Omsk hemorrhagic
fever, and Kyasanur Forest disease viruses.
HFVs as Biological Weapons
• Some HFVs are considered to be a significant threat for
use as biological weapons due to their potential for
causing widespread illness and death.
• Because of their infectious properties, associated high
rates of morbidity and mortality, and ease of person-to-
person spread, Ebola, Marburg, Junin, Rift Valley fever,
and yellow fever viruses have been deemed to pose a
particularly serious threat, and in 1999 the HFVs were
classified as category A bioweapons agents by the CDC.
SIGNS AND SYMPTOMS
• Diagnosis of VHF is based on clinical presentation of
symptoms and confirmed by laboratory testing.
• Following an aerosol dissemination of any of the HFVs of
concern, cases would likely appear within 2 to 21 days
after exposure, depending on the specific virus involved.
• Patients would present with fever, rash, body aches,
headaches, and fatigue; internal and external bleeding
could occur later.
IS BIOLOGICAL WARFARE
TECHNIQUE IS NEW?
INSTEAD IT IS A PRIMITIVE WAR
TECHNIQUE
• ROMANS: used dead animals to foul enemy’s water.
• TARTARS: catapulted dead bubonic plague victims.
• BRITISH – FRENCH –INDIAN WAR: gifts of small
pox infected blankets were provided by Britishers.