Biological Agents: Anthrax, Smallpox, Plague, Toxins, and Surveillance Practice Questions

25 multiple-choice questions on Biological agents: anthrax, smallpox, plague, toxins, and surveillance for paramedic and EMT students, from Chapter 51 (Terrorism Response). Read each question, pick your answer, then tap Show answer to check it and read the explanation.

25 practice questions

1. Compared with chemical agents, biological agents used as weapons usually:

   1. A. Cause illness after an incubation period
   2. B. Cause signs within seconds of being released
   3. C. Leave a visible cloud or oily residue
   4. D. Have strong odors that warn the victims
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   Answer: A. Cause illness after an incubation period

   Bacteria and viruses must multiply before illness appears, so victims of a covert release may be far from the scene when they become ill. Immediate signs and visible residue point to a chemical agent.

2. Which of these biological agents poses the greatest risk of person-to-person spread?

   1. A. Anthrax
   2. B. Tularemia
   3. C. Ricin toxin
   4. D. Smallpox
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   Answer: D. Smallpox

   Smallpox spreads easily from person to person by respiratory droplets and contact, which is why a single case is a public health emergency. Anthrax is tempting because it is the best-known bioweapon, but it does not spread between people.

3. A postal worker had fever, aches, and a dry cough for 2 days, then felt better briefly before sudden severe dyspnea and shock. The ED chest x-ray shows a widened mediastinum. The most likely cause is:

   1. A. Pneumonic plague
   2. B. Inhalational anthrax
   3. C. Influenza viral pneumonia
   4. D. Inhaled ricin
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   Answer: B. Inhalational anthrax

   Inhalational anthrax starts like the flu, may seem to improve, then progresses rapidly to respiratory failure and shock; a widened mediastinum from swollen lymph nodes is a classic clue. Pneumonic plague causes a rapidly worsening pneumonia with bloody sputum rather than a widened mediastinum.

4. A coworker of a patient with inhalational anthrax asks whether she caught it from him. You should explain that anthrax:

   1. A. Spreads by coughing, much like tuberculosis
   2. B. Spreads through casual contact
   3. C. Is not spread from person to person
   4. D. Spreads by shared drinking glasses
   Show answer

   Answer: C. Is not spread from person to person

   People become infected by spores from the source, such as a contaminated letter, not from another patient, so standard precautions are enough for patient care. The coworker may still need prophylaxis if she was exposed to the same source.

5. Four days after opening a letter containing white powder, a man has a painless sore on his hand that has turned into a black scab surrounded by swelling. This is most likely:

   1. A. A spider bite
   2. B. An early smallpox lesion
   3. C. Cutaneous anthrax
   4. D. A sulfur mustard burn
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   Answer: C. Cutaneous anthrax

   Cutaneous anthrax begins as an itchy bump that becomes a painless ulcer with a black eschar and surrounding edema. A brown recluse bite is usually painful, and there is no history of a spider.

6. An office worker opens an envelope, and white powder spills onto her desk. She has no symptoms. The best initial actions are to:

   1. A. Sweep up the powder and bag it for the police
   2. B. Leave it, close off the room, and wash her hands
   3. C. Give ciprofloxacin at once and release her from scene
   4. D. Blow the powder off her clothes with clean air
   Show answer

   Answer: B. Leave it, close off the room, and wash her hands

   Leaving the powder undisturbed, isolating the area, and washing with soap and water limit spread while trained teams test the material. Sweeping or blowing the powder can make spores airborne.

7. Post-exposure prophylaxis for people exposed to inhaled anthrax spores commonly uses:

   1. A. Ciprofloxacin or doxycycline for 60 days
   2. B. Penicillin by mouth for about 7 to 10 days
   3. C. Oseltamivir by mouth for 5 days
   4. D. Acyclovir by mouth for 10 days
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   Answer: A. Ciprofloxacin or doxycycline for 60 days

   Spores can remain dormant in the lungs for weeks, so oral antibiotics such as ciprofloxacin or doxycycline are given for 60 days, often with the vaccine. Oseltamivir and acyclovir are antivirals and have no effect on anthrax bacteria.

8. A febrile 30-year-old has a rash that began on the face and arms. All lesions are firm, deep pustules at the same stage, and some are on his palms. This rash most suggests:

   1. A. Chickenpox
   2. B. Measles
   3. C. Hand-foot-mouth
   4. D. Smallpox
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   Answer: D. Smallpox

   Smallpox lesions are deep, firm, all at the same stage, and most dense on the face and extremities, including the palms and soles. Chickenpox lesions appear in crops at different stages, mostly on the trunk.

9. EMS crews caring for a patient with suspected smallpox should wear:

   1. A. An N95, gown, gloves, and eye protection
   2. B. A surgical mask and gloves
   3. C. Gloves, with good handwashing
   4. D. A fully encapsulated Level A suit with its own air
   Show answer

   Answer: A. An N95, gown, gloves, and eye protection

   Smallpox needs airborne and contact precautions: a fit-tested N95 or PAPR, gown, gloves, and eye protection, with the patient masked if tolerated. A surgical mask does not protect against airborne spread.

10. A patient with smallpox becomes most contagious:

    1. A. During the incubation period
    2. B. After the scabs have fallen off
    3. C. Weeks after the rash fades
    4. D. When the rash first appears
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    Answer: D. When the rash first appears

    Smallpox is most contagious during the first week of rash, when mouth sores shed large amounts of virus. People are not contagious during the incubation period, which is why early isolation of rash cases is so effective.

11. A paramedic learns that a patient she cared for 2 days ago, without respiratory protection, has confirmed smallpox. She feels well. Regarding smallpox vaccine, she should be told that:

    1. A. It is too late to help once a day has passed
    2. B. Given now, it can still prevent or ease illness
    3. C. It should wait until she first develops a fever
    4. D. It must wait until a blood test confirms infection
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    Answer: B. Given now, it can still prevent or ease illness

    Smallpox vaccine given within about 3 days of exposure may prevent disease or make it much milder, and given at 4 to 7 days it likely still offers some protection; this is the basis of ring vaccination of contacts. Two days after exposure she is well inside that window. The benefit does not end after 24 hours. Waiting for fever or a lab test would waste the window, because vaccine given after illness begins does little.

12. Pneumonic plague is a concern for responders because it:

    1. A. Requires a flea bite to spread
    2. B. Is carried in drinking water
    3. C. Spreads by respiratory droplets
    4. D. Is spread through blood contact
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    Answer: C. Spreads by respiratory droplets

    Unlike bubonic plague, which is spread by flea bites, pneumonic plague spreads between people by droplets, so crews need droplet precautions and the patient should wear a mask. Flea bites are the natural route for the bubonic form.

13. Dozens of previously healthy adults develop high fever, chest pain, and cough with bloody sputum, followed by rapid respiratory failure, 2 to 3 days after attending an outdoor festival. The weaponized agent to suspect is:

    1. A. Pneumonic plague
    2. B. Cutaneous anthrax
    3. C. Botulinum toxin
    4. D. Sulfur mustard
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    Answer: A. Pneumonic plague

    Aerosolized plague causes a fulminant pneumonia with bloody sputum within days. Botulinum toxin causes descending paralysis without fever or bloody sputum.

14. Tularemia is considered a potential bioweapon because it:

    1. A. Spreads very easily from person to person
    2. B. Causes illness within a few minutes
    3. C. Survives boiling water for hours
    4. D. Can infect people with very few organisms
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    Answer: D. Can infect people with very few organisms

    Francisella tularensis is highly infectious when inhaled, needing as few as 10 organisms, and can cause severe pneumonia. It is not spread between people, which is the most common misconception.

15. Over 2 days, a dozen people who attended the same arena event develop double vision, drooping eyelids, slurred speech, and trouble swallowing. They are alert and afebrile, with dry mouths and sluggish pupils. The agent to suspect is:

    1. A. Sarin vapor
    2. B. Pneumonic plague
    3. C. Botulinum toxin
    4. D. Ricin toxin
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    Answer: C. Botulinum toxin

    Symmetric cranial nerve palsies (double vision, ptosis, slurred speech, trouble swallowing) in alert, afebrile people who shared a location point to botulism; an aerosol release would produce a cluster like this a day or more later, followed by descending paralysis that can stop breathing. Notify public health at once; antitoxin is released through the CDC. Sarin causes pinpoint pupils, heavy secretions, and twitching within minutes, not a dry mouth days later. Pneumonic plague causes high fever and pneumonia with bloody sputum. Inhaled ricin causes fever, cough, and pulmonary edema, not cranial nerve palsies.

16. A hospital asks whether family members of patients with botulism from an aerosol attack must be isolated. You should know that botulinum:

    1. A. Spreads by droplets for about 2 weeks
    2. B. Is a toxin and is not contagious
    3. C. Spreads by touching the skin
    4. D. Spreads in the patient's urine
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    Answer: B. Is a toxin and is not contagious

    Botulinum is a toxin, not a living organism, so it does not spread between people; only those exposed to the source are at risk. Standard precautions are enough for patient care.

17. Several hours after inhaling a powder mailed to his office, a man has fever, cough, chest tightness, and worsening pulmonary edema. Testing finds a toxin from castor beans. Treatment is:

    1. A. Atropine and pralidoxime autoinjectors
    2. B. Antitoxin given at once by IV
    3. C. Supportive care; there is no antidote
    4. D. Hydroxocobalamin 5 g IV push
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    Answer: C. Supportive care; there is no antidote

    Ricin stops protein synthesis in cells, and no antidote or antitoxin exists, so care is airway support, oxygen, and fluids. An antitoxin exists for botulism, which is why that distractor is tempting.

18. Viral hemorrhagic fevers such as Ebola and Marburg cause their life-threatening effects mainly by:

    1. A. Paralyzing the diaphragm and breathing muscles
    2. B. Blistering the skin and airway
    3. C. Blocking oxygen use in the cells
    4. D. Damaging blood vessels and clotting
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    Answer: D. Damaging blood vessels and clotting

    These viruses injure the vessel lining and disrupt clotting, leading to bleeding, fluid leak, and shock. Paralysis of the breathing muscles is the pattern of botulism, not hemorrhagic fever.

19. Samples from a suspected biological attack are identified through a system of state and federal public health laboratories called the:

    1. A. Laboratory Response Network
    2. B. National Disaster Medical System
    3. C. Strategic National Stockpile
    4. D. Metropolitan Medical Response System
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    Answer: A. Laboratory Response Network

    The Laboratory Response Network links sentinel, state, and CDC reference labs so suspected agents can be confirmed quickly and consistently. The Strategic National Stockpile supplies drugs and equipment; it does not perform the testing.

20. Your crew transports six patients from one apartment building in 2 days, all with fever, cough, and rapid respiratory decline. The best action is to:

    1. A. Treat each case as unrelated pneumonia
    2. B. Report the pattern per agency policy
    3. C. Wait for the hospital to contact you
    4. D. Quarantine the building on your own
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    Answer: B. Report the pattern per agency policy

    EMS is often first to see a cluster, and reporting it to medical direction and public health can speed recognition of an outbreak or attack. Treating each case as unrelated is the error that lets a covert release go undetected.

21. In a large anthrax release, mass prophylaxis is delivered to the public mainly through:

    1. A. Local EMS ambulance units
    2. B. Points of dispensing (PODs)
    3. C. Private physicians' offices
    4. D. Hospital emergency departments
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    Answer: B. Points of dispensing (PODs)

    Public health sets up PODs in schools and other large sites to give antibiotics to thousands of people quickly. Sending the worried well to EDs would overwhelm the hospitals needed for the sick.

22. After a large biological attack, the Strategic National Stockpile can deliver its first push package of drugs and supplies within about:

    1. A. 12 hours
    2. B. 1 hour
    3. C. 3 to 5 days
    4. D. 2 weeks
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    Answer: A. 12 hours

    The SNS keeps push packages ready to reach any US location within about 12 hours of a federal decision to deploy. One hour is too fast for air delivery, so local supplies must cover the first hours.

23. The CDC places anthrax, smallpox, plague, botulism, tularemia, and viral hemorrhagic fevers in Category A because they:

    1. A. Are the agents most often used in past attacks
    2. B. Have no available treatment or vaccine
    3. C. Spread easily or kill many people
    4. D. Act within minutes of exposure
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    Answer: C. Spread easily or kill many people

    Category A agents pose the highest risk to national security because they can be easily spread or passed person to person, cause high death rates, and could cause public panic. Several have vaccines or effective antibiotics, most have never been used in an attack, and they cause illness after hours to days rather than minutes.

24. The early phase of inhalational anthrax is often mistaken for:

    1. A. Food-borne gastroenteritis
    2. B. An allergic reaction
    3. C. Heat exhaustion
    4. D. Influenza or a bad cold
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    Answer: D. Influenza or a bad cold

    Early inhalational anthrax causes fever, aches, fatigue, and a dry cough, much like the flu, which delays diagnosis. Runny nose and sore throat are less common with anthrax, a clue that helps tell them apart.

25. Which finding would most suggest that an outbreak of illness is deliberate rather than natural?

    1. A. A rare disease with no natural source
    2. B. A rise in flu cases in midwinter
    3. C. Food poisoning after a large church picnic
    4. D. Measles among unvaccinated students
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    Answer: A. A rare disease with no natural source

    Cases of a disease that is rare in the area, out of season, or without the usual animal or travel exposure, such as inhalational anthrax in a city office, point to a deliberate release. A winter flu rise is expected and does not raise suspicion by itself.