Bioterrorism: Practical Aspects Keith S. Kaye, MD, MPH.

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Bioterrorism: Practical Aspects Keith S. Kaye, MD, MPH

Transcript of Bioterrorism: Practical Aspects Keith S. Kaye, MD, MPH.

Bioterrorism:

Practical Aspects

Keith S. Kaye, MD, MPH

Overview

• History and Overview of Bioterrorism

• Smallpox

• Update on Anthrax

• What to expect in event of a Bioterrorism threat

• What can you do to help?

Bioterrorism: History• 1346, Kaffa: Attacking Mongols catapulted

cadavers of plague victims into city• 1710: Russians used plague victims against

Swedes• 1767: French and Indian War: Blankets from

smallpox hospital provided to Native Americans – resulted in epidemic of smallpox

• World War I: Germany sent infected horses and mules into Allied lines

• World War II: Japanese military unit 731 killed thousands of Chinese in Ping Fan, Manchuria, with various agents, including Anthrax

• 2 incidents in US over past 20 years involving intentional bacterial contamination of food

United States Bioweaons Program

• 1942 established at Camp Detrick, MD

• 1950 biological simulant sprayed over San Francisco

• 1966 biological simulant sprayed in New York City subway system

• 1969 President Nixon suspends offensive program

• 1972 U.S, U.K., Soviet Union sign Biological Weapons Convention

Soviet Union Bioweapons Program

• Massive program• Many details known through defection of

high-ranking scientist• Weaponized numerous biological agents• Much of offensive research took place

after signing biological weapons treaty• After dissolution of Soviet Union

leaks/dissmination of scientists (known) and bioterrorism agents (suspected)

Difficulties in Cultivating Biological Weapons

• General difficulties in weaponizing a biologic agent– Ability to procure a virulent strain (e.g., anthrax,

tularemia)

– Ability to culture large amounts of the agent

– Ability to process agent into a suitable form (e.g., anthrax spores)

– Ability to safetly handle and store the agent (may be difficult for hemmorhagic fever viruses)

Why Biological Weapons?

• Although challenging to develop, still easier and cheaper to obtain than nuclear weapons

• Soviet scientists with expertise defected to rogue nations

• Potential to cause destruction and hysteria

Smallpox• Virus with person-to-person

transmission; rash similar to chicken pox, but can be easily differentiated

• Naturally occurring disease eradicated in 1977

• Routine immunization in US stopped in 1972

• US and Russia known to have smallpox stocks; but concerns that other countries have Smallpox as well

Smallpox (cont)

• Vaccine exists and is effective

• More vaccine is being made

• No imminent bioterrorism threat for smallpox, but we want to be prepared

• Routine vaccination will probably not be reinstated unless new cases emerge

• Stores of vaccine would be made available for control of outbreaks (bioterrorism)

Bacillus anthracis (Anthrax)

• Bacterium

• Gram positive bacillus• 2 forms, vegetative and spore

• vegetative cells found in anthrax lesions

• spores found in the soil

• Disease• animals - sheep, goats, cows

• naturally occurring disease: human get disease from animals

Anthrax• Prior to 2001, no successful bioterrorist

attacks

• Known to be stockpiled by Iraq and possibly by former Soviet states

• Outbreak due to accidental release, Sverdlovsk (Ekaterinberg, USSR 1979)

• Increase in hoaxes in US, late 1990s

Antrhax: Clinical Diseases

• Cutaneous– Spores enter through cuts/abrasions

• Inhalational– Spores inhaled– NO PERSON-PERSON SPREAD!!!

• Gastrointestinal– Infected meat ingested

• Incubation period generally 1-12 days

Cutaneous Anthrax

• Inoculation of spores into cut/abrasion– Lesions typically on hand/arm or face

• Small pruritic papule ulcer surrounded by vesicles (24-48h) black eschar

• Patients typically have local edema, +/- lymphadenopathy, fever and will feel ill

• Antibiotic treatment extremely effective

Inhalation Anthrax: Manifestations

• First stage: insidious onset (1-4 d)– Malaise– Fatigue– Myalgia– Nonproductive

cough– Precordial pressure– Fever

• Second stage: rapid deterioration (24 h)– Acute dyspnea– Cyanosis– Stridor– Fever– Mediastinal

hemorrhage– CxR: Mediastinal

widening– Meningismus– Septic Shock– Coma

US Anthrax Cases as of November 9, 2001

• Inhalational-10– Florida: 2 (1 fatality)–Washington DC: 5 (2 fatalities)– New Jersey: 2 – New York: 1 (1 fatality)

• Cutaneous-12– New York: 7– New Jersey: 5

Clinical Symptoms of 10 Inhalational Anthrax Cases, U.S., 2001

• Almost all had links to contaminated mail (postal workers and press)

• Median age 56 yrs (range 43-73)• All presented with fever, chills, malaise 10/10• Cough (often dry) 9/10• Nausea and vomiting 8/10• Paucity of cold symptoms, sore throat• All 10 patients had abnormal CxR findings• All not receiving antibiotics had + blood cultures• 6/10 survived

US Anthrax Cases to Date November 9, 2001

• Source of exposure known for almost all cases (mail)

• ~32,000 people in US were started on antibiotics for prophylaxis in past several weeks and in 5000 persons a full 60 day antibiotic course was advised.

• 95/490 patients (~20%) receiving prophylaxis reported one or more side effect in one survey

Inhalation Anthrax: Summary Points

• Almost all patients had clear epidemiologic links to anthrax source (investigations ongoing)

• All patients had prodromal illness with fever– Cold symptoms, sore throat usually absent

• Anthrax will readily grow in cultures• Anthrax is much more treatable than previously

thought• Anthrax is NOT communicable, person to person• Currently NO anthrax cases in NC• Harmful effects of unnecessary antibiotics are

common

GUIDELINES FOR MANAGEMENT OF POTENTIALLY THREATENING LETTERS

• Do not open suspicious letter/package• Do not shake/empty• Do not show to others (don’t sniff, touch etc)• Place package on stable surface and alert others in

the area• Leave area, close doors, prevent others from

entering, shut off ventilation system• Wash hands/change clothes• Contact supervisor, local law enforcement via 911• If possible, create list of persons in room (give to

public health personnel)• www.bt.cdc.gov

Recommendations for Mail Handlers

• New recommendations

• Major focus is use of gloves for workers handling mail

• Respiratory protection (N95 mask) for workers with mail sorting machinery

• Follow news for further updates

What to expect in the event of a Bioterrorism Threat

• Hospitals have plans, but CDC, State will organize response

• Patients might be triaged at locations outside of local emergency rooms

• Dispensing of antibiotics and vaccines will be organized through CDC/State, but will utilize local hospitals for support

• Potential restriction of travel, movement; lock down of hospitals (Smallpox)

How Can You Help ?

• Don’t crowd emergency rooms if you are not acutely ill– Talk with your primary care physician

• Antibiotics not helpful unless there is a clear indication

• No role for nasal swabs as diagnostic tool!

• Have a high index of suspicion for atypical skin lesions, clusters of cases among friends, co-workers

How Can You Help ? (2)

• Report suspicious letters/packages/powders to police/FBI, HAZMAT teams (911)

• Report suspicious illnesses/clusters to your physician and county or State Health Department– Infection Control within the hospital

• Follow the news: web sites for reliable, helpful information:– www.bt.cdc.gov– http://www.usps.com/

How can you help (3)• Increased level of awareness, but . . .• Remain calm– No cases in North Carolina (and in most states)– There are effective ways to prevent and treat

anthrax once a threat has been recognized• Flu season is upon us – Let your doctor know if you develop flu symptoms– No reason to suspect anthrax, with no anthrax in

NC– If you are ill, and feel you might have had an

exposure, let your physician know– Even if you have had flu shot or a negative flu test,

you can still might get the flu, or an illness like the flu!