2. BIOLOGICAL DISASTERS PREVENTION AND
MITIGATION
BY
MENAKA KANNAIYAN
TAM-14-012

3. BIOLOGICAL DISASTERS
• A biological disaster may have a considerable impact in terms
of human life, disability, quarantine, treatment costs and
disposal of deceased persons in addition to long term
environmental and economic consequences.
• It is important to recognise that biological disasters may be
naturally occurring events (e.g. an influenza pandemic) or a
deliberate event (biological terrorism).

4. • Biological disasters of natural origin are largely the result of the
entry of a virulent organism into a congregation of susceptible
people living in a manner suited to the spread of the infection.
• Anthrax- spore dispersal in the air.
• Small pox-aerosols.
• Typhus and plague-lice, fleas, rodents etc.
• Epidemic spreads locally and dies down if the contagion is
localized.
• Diseases have spread widely, even across national boundaries

5. • Disasters occurred-environmental factors conducive
• Black death occurred- increase in number of rats.
• Cholera attained a pandemic form-causative agent entered
urban areas which had inadequate sanitation facilities

6. BIOLOGICAL AGENTS AS CAUSES OF
MASS DESTRUCTION
• Highly virulent agents have the potential of infecting large
numbers- infectious chains.
• The potential of some infectious agents is nearly as great as that
of nuclear weapons.
• Weapon of mass destruction(WMD): Nuclear ,Biological and
Chemical.

7. TRENDS FAVOURING BIOLOGICAL WEAPONS
• Low cost and wide spread availability .
• More efficient in terms of coverage/ kg of payload.
• Advances in biotechnology have made production easy.
• Agents are largely natural pathogens and simulate existing
diseases.
• Have an unmatched destructive potential.

8. • Technology for dispersing biological agents- sophisticated.
• The lag time between infection and appearance of symptoms is
longer than with chemical exposures.
• Lethal biological agents can be produced easily and cheaply.

9. SOURCES OF BIOLOGICAL AGENTS:
• Any human, animal or plant pathogen can cause a epidemic or
biological weapon.
• The deliberate intention or action to cause harm or biological
attack.
• Incident in USA where members of a religious cult caused
gastroenteritis by the use of Salmonella typhimurium (common
natural pathogen).

10. METHODS OF DESSIMINATION OR DELIVERY
• Aerosols-biological agents are dispersed into the air forming a fine
mist that may drift for miles.
• Animals-fleas, mice, flies , mosquitoes and livestock.
• Food and water contamination-some pathogenic organisms and
toxins may persist in food and water supplies.
• Person to person-Small pox , Plague and the Lassa viruses.

11. TYPES OF BIOLOGICAL AGENTS
• There are 3 categories of biological agents potential enough to
cause mass casualties( centre for disease control and prevention)
• Category A, B and C.
• Those in category A have greatest potential for fear and disruption
and most significant public health impacts.

12. CATEGORY A:
 Easily disseminated or transmitted from person to person.
 High mortality.
 Requires special action for public health preparedness.
 Viruses: Variola major(small pox), Filo viruses(Ebola, Marburg),
Arena viruses(Lassa, Junin).
 Bacteria: Bacillus anthracis(anthrax), Yersinia pestis(plague),
Francicella tularensis(tularemia).
 Toxins : Clostridium botulinum toxin(botulism)

13. CATEGORY B:
 Moderately easy to disseminate.
 Moderate to low mortality.
 Require improved diagnostic capacity and enhanced surveillance.
 Viruses: Alpha viruses
 Bacteria: Coxiella burnetti (Q fever), Brucella species
(brucellosis).
 Toxins: Ricinus communis( caster beans) ricin toxin,
staphylococcus entero toxin B.
 Food and water borne pathogens: Salmonella spp., Vibrio
cholerae.

14. CATEGORY C:
• Viruses: Nipah, hanta viruses, tick borne hemorrhagic fever
viruses, tick borne encephalitis viruses, yellow fever.
• Bacteria: Multi drug resistant Mycobacterium tuberculosis.

15. ANTHRAX DISEASE
• The disease anthrax is caused by non motile, gram positive
Bacillus anthracis.
• It has been a scourge of cattle and other herbivores for
centuries.
• During the industrial revolution , the inhalation form was first
recognized as an occupational pulmonary disease in workers in
the wool industries of Europe.
• Anthrax makes an ideal biological weapon.
• The inhalation form of disease is highly lethal.
• The spores can maintain for decades they can be milled into
ideal particle size for optimum infection of human respiratory
tract.

19. SMALL POX DISEASE
• If used as a biological weapon, smallpox represents a serious
threat to civilian population because of its case fatality rate of 30%
or more among unvaccinated persons and the absence of specific
therapy.
• Small pox has long been considered as the most devastating of all
infectious diseases and today its potential for devastation is far
greater than at any previous time

21.  Smallpox virus is a member of genus Orthopox virus, and it is
closely related to the viruses causing cowpox vaccinia and
monkey pox.
 It is one of the largest DNA viruses known and it has a brick like
appearance on electron microscopy.
 Transmission risk increases if the patient is coughing or sneezing
or if he or she has hemorrhagic disease.

22. • Typically, the virus enters the respiratory mucosa and then travels
to regional lymph nodes where it replicates.
• The incubation period from infection to onset of rash ranges from
7 to 17 days. Small pox scabs remain infectious until they fall off,
whereas chicken pox is no longer infectious once the lesions are
crusted.

23. PLAGUE DISEASE
• The mere mention of the world plague conjures up many images
because has already demonstrated a historical potential to kill
millions of people across the globe .
• It is a disease that results from infection by non- motile gram
negative coccobacillus Yersinia pestis.

24.  Following the bite of an infected flea, plague bacilli are carried via
the lymphatic to the regional lymph nodes where they multiply
exponentially.
 This is the only weapon besides smallpox which can cause
devastation beyond those persons who are initially infected.

25. • Botulinum or botulism toxins are deadly.
• A toxin is any toxic substance that can be produced in an animal
plant or microbe.
• The toxins produce serious disease in human beings.
• Many natural toxins can be produced by chemical synthesis or can
be expressed artificially.
• Toxins are natural and non volatile and generally do not penetrate
intact skin, which happens in case of chemical weapons.
BOTULINUM

26. • There are different type of toxins and they are immunologically
distinct, meaning that antibodies developed against one do not
cross react against others.
• Humans can be intoxicated either by oral means , inhalation, or
wound infection.
• The incubation period ranges from as short as 24 to 36 hours to
several days from the time of infection.

27. TULAREMIA
• Tularemia is caused by Francisella tularensis, which is a non-
motile, gram-negative cocco bacillus.
• Tularemia is a zoonotic disease acquired in a natural setting by
humans through skin or mucous membrane contact with the body
fluids or tissues of infected animals or from being bitten by
infected deerflies, mosquitoes or ticks.
• It can remain viable for weeks in environment or in animal
carcasses and for years if frozen.

28. Francisella tularensis

29. • After an incubation period of 2 to 10 days, pneumonia symptoms
develop associated with weight loss and non productive cough.
• The drug of choice for treatment is streptomycin with other
aminoglycosides.

30. EBOLA
• Ebola virus / Zaire ebola virus is one of the four ebola viruses known to
cause disease in humans.
• It has the highest case-fatality rate of these ebolaviruses, averaging 83%
since first described in 1976, although fatality rates up to 90% have been
recorded in one epidemic (2002–03).
• There have also been more outbreaks of Zaire ebola virus than of any other
ebolavirus. The first outbreak occurred on 26 August 1976 in Yambuku.
• The first recorded case was Mabalo Lokela, a 44-year-old schoolteacher.
The symptoms resembled malaria, and subsequent patients
received quinine.
• Transmission has been attributed to reuse of unsterilized needles and close
personal contact, body fluids and places where the person has touched.

31. SYMPTOMS OF EBOLA
• Bleeding from mouth ,nose, ears.
• Increased sensitivity to pain on the skin.
• Genital swelling.
• Conjuctivitis.
• Rashes all over the body.
• Reddening of roof of the mouth.

33. EBOLA INFECTION

34. MAJOR EVENTS ACROSS THE GLOBE
• Biological warfare has a long history of mass destruction-
epidemic and pandemic diseases.
• Mycotoxins have been reported to be used in Afghanisthan.
• The red Indians in North America were given the smallpox
infected blankets.
• In 2001 USA experienced biological attacks involving the
intentional distribution of Bacillus anthracis spores through the
postal system. It created the threat for bioterrorism.

35. • Medical advances reduced the damages from some of
infectious diseases, yet many remain to be conquered.
• Highly pathogenic avian influenza, a disease in birds occurring
repeatedly since ancient times, is now found worldwide.
• The World Health Organization (WHO) announced on
February 15, 2007 that of 273 bird flu victims in 11 countries
in Asia, the Middle East, and Africa, 166 have died.

36. • Since bird flu does not spread easily to human beings, the number
of victims is limited.
• The worst historically recorded ones involved Spanish flu, which
started in 1918 during World War I among French and German
soldiers and spread globally, resulting in 20 million to 60 million
deaths.
• Spanish flu - said to have been named after its effects on the
Spanish royal family - is known to have caused the highest number
of deaths of any single infection.

37. DOCUMENTED INTENTIONAL USE OF BIOLOGICALS:
• Dispersal of anthrax spores due to accident in production unit in
USSR caused 68 deaths in 1979.
• In 1984, Osho followers used Salmonella typhimurium in salad in
a restaurent in Oregaon , USA leading to 751 cases.
• Anthrax spores through postal envelopes in USA in Oct-Nov 2001
leading to 22 cases and 5 deaths.

38. PRESENT STATUS AND CONTEXT:
• Plague which has assumed epidemic proportions in the early to
mid 19th and 20th centuries, has nearly been eliminated.
• SARS outbreak in 2003 caught the attention of the world-
spread of a disease from a single hospital case to a global
pandemic in less than 3 months.

39. • Similarly, the outbreak of avian influenza among poultry in
Nandurbar and Jalgaon districts of Maharastra and adjoining
districts of Gujarath and Madhya pradesh (2006) saw the
poultry industry plummet.

40. • The 1918 influenza pandemic killed an estimated 7 million
people in India.
• Slow , evolving epidemics such as HIV/ AIDS- socio –
economic disruption.
• Emerging and re-emerging diseases , notably SARS, avian
influenza, Nipah virus, leptospirosis, dengue, Chickengunya,
and Rickettsial are also posing serious threats.

41. PREVENTION AND MITIGATION MEASURES OF
BIOLOGICAL DISASTERS
• The general population should be educated and made aware of
the threats and risks associated with it.
• Only cooked food and boiled/ chlorinated/ filtered water
should be consumed.
• Insects and rodent control measures must be initiated
immediately.
• Clinical isolation of suspected and confirmed cases is
essential.

42. • Therefore a network of specialized laboratories should be
established for a confirmatory laboratory diagnosis.
• Existing disease surveillance system as well as vector control
measures have to be pursued more rigorously.
• Mass immunization programme in the suspected area has to be
more vigorously followed up.

43. FUTURE PLAN
• Since vaccines against a number of potential biological
warfare agents have already been in use,mass immunization of
the population would be done on a priority basis.
• Vaccines against remaining agents should have to be
reasearched and developed.
• Mass public awareness before, doing and after such an attack
must be emphasized upon.