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Bioterrorism Lecture

 Bioterrorism Lecture


Objectives 

 To understand the concept of terrorism 

 To understand the rationale for the use of biological agents as terrorist weapons 

 To describe the characteristics of those biologic agents thought to be the choice of terrorists


Introduction

 Bioterrorism is one form of terrorism. Terrorism is defined as the unlawful use of force or violence against persons or property to intimidate or coerce a government or civilian population in the furtherance of political or social objectives.

 Terrorists use weapons of mass destruction. These are destructive devices that include bombs, missiles, poison chemicals, disease organisms, radiation or radioactivity at levels dangerous to human life. 

 The 9/11 Commission Report stated referring to the terrorist threat…… 

 ………..we are not safe 

 Time is not on our side…………..


 Biologic agents are likely to be used by terrorists as weapons because: 

 They are capable of damaging populations, economies, and food supplies 

 Certain agents are inexpensive to make 

 They can be directed at a small group of people or an entire population 

 They can be used to attack people, economies and food supplies 

 They cause fear, panic and social disruption 

Characteristics of biological agents that could be used as bioterrorism agents 

 They have a wide range of effects 

 They are obtained from nature 

 They are easily made by relatively unsophisticated methods 

 They are invisible to the senses 

 Their effects may be delayed 

 They can produce mass casualties


DIFFERENCES BETWEEN A BIOLOGICAL ATTACK AND A NATURAL OCCURRENCE 

 A biological terrorist attack may mimic a large-scale naturally occurring disease outbreak. There are differences. A biological attack: 

 Results from a deliberate act 

 Will be treated as a crime scene 

 May not be immediately recognized 


BIOLOGICAL ATTACK VS. NATURAL OCCURRENCE 

 It May be preceded by verbal or written threats from a terrorist group 

 May find abandoned spray devices after their release 

 Claims by a terrorist group to have released a biologic agent 

 May result in contamination of critical facilities 

 May expand rapidly from different source cases 

 Will cause widespread public panic 


ROUTES OF ENTRY INTO THE HUMAN BODY 

 Ingestion 

 Dermal penetration 

 Inhalation


AEROSOL INHALATION 

 The use of aerosols is an efficient way to affect the maximum number of people with a single attack. 


BIOWEAPONS RECENT HISTORY 

 Bioweapons have a long history. Recent uses include: 

 U.S, Canada, Great Britain, Japan, and the U.S.S.R experiment with anthrax during World War II (W.W.II) 

 In 1991, Iraq threatens the use of bioweapons against U. S. troops in the Persian Gulf war 

 Post-W.W.II, NATO and the Warsaw Pact nations had bioweapons programs

 In 1969, U. S. unilateral decision to destroy bioweapons 

 In 1972, Bioweapons Convention was created in which U. S. and U. S. S. R. were signatories 

 Possible/probable active offensive bioweapons programs in N. Korea, Iran, China, Egypt, Algeria, India, Pakistan, Syria, Israel

 In 1984, the Bhagwan cult poisons Oregon salad bars with salmonella-751 people sick 

 In 1995, Aryan Nation orders plague bacteria from a supply house in Maryland, and Minnesota Patriots Council members convicted for planning ricin use in an assassination attempt 


BIOLOGICAL AGENTS 

 There are several types of agents. They are classified as: 

 Bacteria 

 Rickettsia 

 Viruses 

 Biotoxins 




Category A Diseases/Agents 

 High-priority agents include organisms that pose a risk to national security because they: 

 can be easily disseminated or transmitted from person to person; 

 result in high mortality rates and have the potential for major public health impact; 

 might cause public panic and social disruption; and 

 require special action for public health preparedness. 


Category B Diseases/Agents 

 The second highest priority agents include those that 

 are moderately easy to disseminate; 

 result in moderate morbidity rates and low mortality rates; and • require specific enhancements of CDC's diagnostic capacity and enhanced disease surveillance. 


Category C Diseases/Agents 

 The third highest priority agents include emerging pathogens that could be engineered for mass dissemination in the future because of :

 availability

 ease of production and dissemination; and 

 potential for high morbidity and mortality rates and major health impact.


BACTERIA 

 Single-celled organisms are capable of causing disease. These agents, grown on culture to produce large quantities, can be modified or “weaponized” for greater destruction 

 Produces inflammation in tissues and/or toxins 

EXAMPLES 

 ANTHRAX  PLAGUE  TYPHOID  CHOLERA  TULAREMIA  Salmonellosis 


RICKETTSIA 

 Vector-borne (ticks, lice, mosquitos) parasitic form of bacteria 

 Diseases are difficult to treat 

 Variants exist worldwide 

EXAMPLES 

 TYPHUS  ROCKY MT. SPOTTED FEVER  Q FEVER  INDIA TICK FEVER  MEDITERRANEAN TICK FEVER


VIRUSES 

 Smaller than bacteria 

 RNA or DNA in a protein coat 

 Use living cells to reproduce 

 Not affected by antibiotics 

EXAMPLES 

 EBOLA  SMALLPOX  LASSA FEVER  INFLUENZA  VIRAL HEPATITIS  VIRAL HEMORRHAGIC FEVERS


BIOTOXINS 

 Are poisonous byproducts of bacteria, fungi, marine animals or plants 

 Do not replicate in the host 

 Are not communicable 

 Highly toxic when delivered as an aerosol 

EXAMPLES 

 BOTULINUM  STAPHYLOCOCCAL ENTEROTOXIN B  RICIN 1

Biological Agents most likely to be used in a terrorist attack 

 Bacteria - anthrax, plague, tularemia 

 Virus - smallpox, viral hemorrhagic fever 

 Biotoxin - botulism


ANTHRAX 

 Infectious agent: Bacillus anthracis – gram +, spore forming bacteria 

 May enter the body from skin (cutaneous), digestive system or by inhalation (most likely route to be used by terrorists)

 Symptoms: itching, lesions, fever, fatigue, non-productive cough, respiratory failure and hemodynamic collapse 

 Transmission: none person to person except with cutaneous 

 Incubation period: 1 to 6 days 

 Mortality: 5 to 20% percutaneous, 80 to 90% inhalation 

 Treatment: antibiotics 

 Prevention: vaccine


PLAGUE 

 In nature, fleas living on rodents spread the infection to humans. As a bioterrorist weapon – inhalation of aerosol leads to pneumonia, sepsis, and infections of bodily organs 

 Infectious agent: Yersinia pestis – a gram neg., non-motile bacillus 

 Maybe bubonic ( infection of lymph nodes) or pneumonic (infection of lungs)or septicemic 

 Symptoms: cough with bloody sputum, fever, chill, shortness of breath

 Transmission: may occur person to person by respiratory droplet inhalation 

 Incubation period: 2 to 3 days 

 Mortality: 50 to 60% 

 Treatment: antibiotics 

 Prevention: vaccine ineffective against aerosol exposure


TULAREMIA 

 A zoonotic, bacterial infection caused by Francisella tularensis, a gram negative coccobacillus 

 In nature, bacteria is commonly found in ticks living on rabbits and transmitted by handling the animal or by a tick bite. Inhalation of aerosol leads to pneumonia and sepsis

 Symptoms: sudden and influenza-like with fever, chills, headache, and nausea 

 Transmission: not usually person to person 

 Incubation period:3 to 5 days(range 1 to 14) 

 Mortality: low unless untreated 

 Treatment: antibiotics if early, vaccine available 

 Prevention: in nature, avoid tick bites and using gloves when handling infected animals 


BOTULISM 

 Infectious agent: Clostridium botulinum – a spore-forming, anaerobic bacillus 

 In nature, maybe foodborne, wound, or intestinal. As a bioterrorist weapon, ingestion or inhalation leads to the production of the neurotoxin and resulting flaccid paralysis

 Symptom: fatigue, weakness, blurred vision, difficulty in swallowing and speaking, descending muscle paralysis and respiratory failure 

 Transmission: none person to person 

 Incubation period: 12 to 72 hours 

 Mortality: most lethal compound per weight 

 Treatment: antitoxins, respiratory support 

 Prevention: vaccine available for types A and B


SMALLPOX 

 Infectious agent: Variola virus - Orthopoxvirus 

 Declared eradicated in 1980, but stockpiles may exist 

 Not naturally acquired. It can be disseminated as an inhaled as an aerosol 

 Symptoms: Fever, muscular rigidity, headaches, and vomiting. Severe cases experience prostration and hemorrhage into the skin and mucous membranes

 The rash appears after about three weeks; progresses from macules (initial skin lesions) to papules to pustular vesicles, to scabs 

 Transmission: may occur person to person by respiratory droplets or skin inoculation. Highly contagious when the rash appears 

 Incubation period: 10 to 12 days 

 Mortality: less than 1% in the minor form and 20 to50 % in the major form 

 Treatment: supportive 

 Prevention: vaccine


VIRAL HEMORRHAGIC FEVERS (VHFs)

 These are highly infectious viral illnesses caused by the Filoviruses (Ebola and Marburg), Arenaviruses (Lassa fever), Bunyaviruses (Congo hemorrhagic fever and Hantaviral disease), and Flaviviruses 

 Symptoms: vary from one type to the next. They include: sudden onset of fever, muscle aches, headache, followed by vomiting, diarrhea, and rash, and internal bleeding 

 Complications: In severe forms, multiorgan failure occurs, primarily due to hemorrhagic and pulmonary complications

 Mode of transmission: handling infected wild animals, but may be used as an aerosol bioterrorist weapon 

 Incubation period: 2 to 21 days 

 Reservoir: gorillas and chimpanzees 

 Transmission: some may be spread person to person by contact with body secretions 

 Mortality: Ebola rates have reached 90% but vary 

 Treatment: supportive 

 Prevention: Avoid contact with infected monkeys or other animal hosts


PREPAREDNESS FOR BIOTERRORISM

  • Build an Emergency Supply Kit.
  • Make a Family Emergency Plan.
  • Check with your doctor to make sure everyone in your family has up-to-date immunizations.
  • Consider installing a High-Efficiency Particulate Air (HEPA) filter in your furnace return duct, which will filter out most biological agents that may enter your house.

During a Biological Threat

The first evidence of an attack may be when you notice symptoms of the disease caused by exposure to an agent. 

In the event of a biological attack, public health officials may not immediately be able to provide information on what you should do. It will take time to figure out exactly what the illness is, how it should be treated and who is in danger.

During a threat:

Watch TV, listen to the radio or check the Internet for official news and information including:

  • Signs and symptoms of the disease
  • Areas in danger
  • If medications or vaccinations are being distributed
  • Where to seek medical attention if you become ill
  • If you become aware of a suspicious substance, quickly get away.
  • Cover your mouth and nose with layers of fabric that can filter the air but still allow breathing. Examples include two to three layers of cotton such as a t-shirt, handkerchief or towel.
  • Depending on the situation, wear a face mask to reduce inhaling or spreading germs.
  • If you have been exposed to a biological agent, remove and bag your clothes and personal items. Follow official instructions for disposal of contaminated items.
  • Wash yourself with soap and water and put on clean clothes.
  • Contact authorities and seek medical assistance. You may be advised to stay away from others or even to quarantine.
  • If your symptoms match those described and you are in the group considered at risk, immediately seek emergency medical attention.
  • Follow the instructions of doctors and other public health officials.
  • Avoid crowds.
  • Wash your hands with soap and water frequently.
  • Do not share food or utensils.

How Prepared Are We?

References/Further Reading


Thank you 



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