2. Overview
1. Definition
2. Biological Agents as Causes of Mass destruction
3. Sources of Biological Agents
4. Methods of dissemination/delivery
5. Types of Biological Agents
6. History: Major Events across the Globe
7. Present status and context
8. Impact of Biological disasters
9. Prevention of Biological disasters
3. Definition
• 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 & plague - lice, fleas, rodents, etc.
• Epidemic spreads locally and dies down if the contagion is
localised
• diseases have spread widely, even across national
boundaries.
4. • Disasters occurred - environmental factors - conducive
• Black Death occurred - increase in no. of rats
• Cholera attained a pandemic form - causative agent
entered urban areas which had inadequate sanitation
facilities.
• Similarly, post WW I, the movement of population -
Spanish influenza virus.
5. 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 (NBC).
6. TRENDS FAVORING BIOLOGICAL WEAPONS
• Low cost and widespread 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
7. • 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.
8. Sources of Biological Agents
• Any human, animal or plant pathogen can cause an
epidemic or biological weapon.
• The deliberate intention/action to cause harm -
biological attack.
• Incident in the USA where members of a religious cult
caused gastroenteritis by the use of Salmonella
typhimurium (Common natural pathogen)
9. Methods of dissemination/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 : Smallpox, Plague, and the Lassa
viruses.
10. Types of Biological Agents
• There are three categories of biological agents potential
enough to cause mass casualties (Center for Disease
Control & Prevention).
• Category A, B & C
• Those in category A have the greatest potential for fear
and disruption and most significant public health
impacts.
11. CATEGORY A
• Easily disseminated or transmitted person-to-person
• High mortality
• Require special action for public health preparedness
• Viruses: Variola major (smallpox), Filo viruses (Ebola,
Marburg), Arenaviruses (Lassa, Junin)
• Bacteria: Bacillus anthracis (anthrax), Yersinia pestis
(plague), Francisella tularensis (tularemia)
• Toxins: Clostridium botulinum toxin (botulism)
12. CATEGORY B
• Moderately easy to disseminate
• Moderate morbidity and low mortality
• Require improved diagnostic capacity & enhanced surveillance
• Viruses: Alphaviruses
• Bacteria: Coxiella burnetii (Q fever), Brucella spp. (brucellosis),
Burkholderia mallei (glanders)
• Toxins: Rinus communis (caster beans) ricin toxin, Clostridium
perfringens episolon toxin, Staphylococcus enterotoxin B
• Food/waterborne pathogens: Salmonella spp., Vibrio cholerae,
E. coli O157:H7, Shigella dysenteriae, Cryptosporidium parvum,
etc.
15. Source: Medical Management of Biological Casualties handbook, Sixth edition, April 2005;
USAMRIID, Fort Detrick Frederick, Maryland
16. • Certain characteristics need to be present for an
organism - potential biological agent for warfare or
terrorist attack.
• Anthrax, smallpox, plague, tularemia, brucellosis and
botulinism toxin - leaders in the field.
• Use of agents that target livestock and crops could be as
devastating as human pathogens - probable economic
impact on the community.
17. History: Major Events across the
Globe
• Biological warfare has a long history of mass destruction
- epidemic and pandemic diseases.
• Limited biological warfare is reported to have been
carried out by Japan during World War-II
• Mycotoxins have been reported to be used in
Afghanisthan
• the Red Indians in North America were given the
smallpox infected blankets
• 2001, the USA experienced biological attacks involving
the intentional distribution of bacillus anthracis spores
through the postal system.
18. Documented Intentional Use of Biologicals
• Japan used plague bacilli in China during 1932-1945
causing 260,000 deaths
• Dispersal of anthrax spores due to accident in production
unit in USSR (Sverdlovsk) caused 68 deaths in 1979
• In 1984, Osho followers used Salmonella typhimurium in
salad in a restaurant in Oregaon, USA leading to 751
cases
• Shigella dysenteriae Type 2 employed in Texas, USA in
1996
• Anthrax spores through postal envelopes in USA in Oct-
Nov 2001 leading to 22 cases and 5 deaths
19. Present status and context
• India accorded significant priority - control & elimination
of diseases - major public health burden.
• Eradication of smallpox in 1975 that accounted for
majority of deaths in 18th and 19th centuries.
• Malaria is another major public health problem - fall in
economic production with over 75 million cases
annually in the early 1950s, which has now been
successfully brought down to two million cases annually
• plague, which had assumed epidemic proportions in
the early to mid 19 th and 20th centuries, has
nearly been eliminated.
20. • Plague outbreak in Surat (1994) with over 1,000
suspected cases and 52 deaths - widespread panic and
mass exodus of people
• 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 three months.
• Though India reported only three, the panic created by
the media was unprecedented.
• Similarly, the outbreak of avian influenza among poultry
in Nandurbar and Jalgaon districts of Maharashtra and
adjoining districts of Gujarat and Madhya Pradesh
(2006) saw the poultry industry plummet.
21. • A still greater threat - possibility of avian influenza
(H5N1) to become a pandemic virus that may kill
millions.
• The 1918 influenza pandemic killed an estimated 7
million people in India.
• Slow, evolving epidemics such as HIV/AIDS - socio-
economic disruption
• Emerging and reemerging diseases, notably SARS,
avian influenza, Nipah virus, leptospirosis, dengue,
Chikungunya and Rickettsial, are also posing serious
threats.
22. • Among the eight to ten globally recognised, most
harmful Trans-boundary Animal Diseases five are
existing in the country, e.g., FMD, PPR, Newcastle
disease, hog cholera and bluetongue.
• India has been successful recently in eradicating
rinderpest
• Highly Pathogenic Avian Influenza (HPAI) (bird flu) has
already invaded the country on two occasions in
successive years 2006 and 2007.
• Through timely intervention - control the potential for a
human pandemic
23. Impact of Biological Disasters
• Bioweapons - ‘the poor man’s nuclear bomb’
• Large scale operation may cost $ 2,000 per sq. km with
conventional weapons,
• $ 800 with nuclear weapons,
• $ 600 with nerve gas weapons and
• $ 1 with biological weapons.
24. • Dispersal experiments have been attempted using non-
pathogenic Bacillus globigii
• An attack on the New York subway system would kill at
least 10,000 people.
• WHO studies show that a 50 kg dispersal on a population
of 500,000 would result in up to 95,000 fatalities.
• In case of smallpox, the emergence of secondary cases
at the rate of 10 times the number of primarily.
• Inevitably, epidemics would break out and social chaos
would ensue.
25. • The economic impact of BT would be a major burden
• Use of Bacillus anthracis would cause losses of $26.2
billion per 100,000 persons exposed, while a less lethal
pathogen, e.g., Brucella suis would cause $477.7 million.
• A BT attack on agriculture can cause as much economic
loss as an attack on human beings.
• The spread of the Parthenium hysterophorus weed - late
1950s along with imported wheat, affected the yield of
fodder crops and became a crop pest
26. Prevention of Biological Disasters
a) Vulnerability Analysis and Risk Assessment
b) Environmental Management
i. Water supply
ii. Personal hygiene
iii. Vector control
iv. Burial/disposal of the dead
c) Prevention of Post-disaster Epidemics
d) Integrated Disease Surveillance Systems
27. e) Pharmaceutical Interventions: Chemoprophylaxis,
Immunisation and Other Preventive Measures
f) Non-pharmaceutical Interventions
i. Social Distancing Measures
ii. Disease Containment by Isolation and Quarantine
Methodologies
g) Biosafety and Biosecurity Measures
