The Anatomy of Bioterrorism: A Glance at the Abyss: The Anatomy of Bioterrorism: A Glance at the Abyss Patrick F. Luedtke MD, MPH
Deputy State Epidemiologist
Utah Department of Health
Objectives:: Objectives: Learn the recent history of massive disease outbreaks in humans tied to biological agents in water, food and air
Understand the epidemiology of bioterrorism as it applies to disease outbreaks in human populations.
Objectives II:: Objectives II: 3. Understand the importance of primary and secondary disease surveillance systems in a “BT world.”
4. Be able to critically appraise the bioterrorism preparations of your facility.
What I Will Cover:: What I Will Cover: What I think we know…
Why I think we know it…
What I think it means…
What I feel we should do…
And just a little “What I think we don’t know…”
Characteristics of BT Outbreaks: What I think we know…: Characteristics of BT Outbreaks: What I think we know… 1. Variable incubation periods for a given agent: no single “lights & sirens” response
2. Critical issue of “the epidemic curve”
(point, propagated, continual source outbreaks)---import of communicability!
Specific disease needs are indeed specific!
The “Big 8”---6 Category A agents plus SARS & Influenza
Why I Think We Know It…: Why I Think We Know It… Water---Milwaukee, March-April 1993
Air---Las Vegas exercise (anthrax, SARS)
Food---Schwan’s ice cream 1994
Agricultural---Monkeypox spring 2003
(Economic: the FMD prototype?)
What I Think It Means: Water: What I Think It Means: Water 1. Milwaukee:
---delayed presentation/variable incubation
---importance of surveillance systems, including novel systems
---lack of “lights & sirens” response need
---point source BT outbreaks may be massive
Cryptosporidiosis in Milwaukee:: Cryptosporidiosis in Milwaukee: Cryptosporidium
Intracellular, protozoan parasite, described 1907
Cause of human diarrhea 1976
Increased importance with onset of HIV/AIDS led to improved diagnostics and recognition as common pathogen
~ 3-4,000 reported cases in U.S./yr (40 states)
Jan-Feb, 1987 – Carroll Co., Ga
Outbreak of cryptosporidiosis – est. 13,000 cases
Contamination of “adequately” treated public water supply
Hayes, et. al. NEJM 1989;320:1372-6
Cryptosporidiosis in Milwaukee: Cryptosporidiosis in Milwaukee April 5, 1993 – citywide shortage of antidiarrheal agents, increased absenteeism among hospital employees, students, and school teachers, shortages of bacterial enteric culture media
April 7 – two laboratories identified cryptosporidium oocysts in stool of 7 adults
Estimated 403,000 cases of watery diarrhea
4,400 hospitalized
Cryptosporidiosis-Milwaukee, Mar-Apr 1993Retrospective identification by telephone survey: 1st laboratory ID (April 7) Outbreak ID (April 5) Cryptosporidiosis-Milwaukee, Mar-Apr 1993 Retrospective identification by telephone survey NEJM 1994;331:161-167
Onset Dates of Human West Nile Virus Cases, Colorado, 2003: Onset Dates of Human West Nile Virus Cases, Colorado, 2003 N=2944 + bird + mosquito + horse + chicken
Epi Curve 8/6/2004: Salmonella: Epi Curve 8/6/2004: Salmonella
What I Think It Means: Air Determined Promise ’03: What I Think It Means: Air Determined Promise ’03 Las Vegas, August 2003
---Several liters of plague slurry released on “The Strip” on a Friday night
---First cases present 36 hours later
---640 Saturday flights in Las Vegas airport
(all over US and 6 other countries)
---Simultaneous presentations throughout US!
(Dr. Thompson’s quote---NORTHCOM)
What I Think It Means: Air: What I Think It Means: Air 2. Florida, anthrax/International, SARS:
---delayed identification may be deadly
---importance of clinician education
---“tiered” surge capacity: the need for
“pre-event” hospital designations
---propagated source outbreaks of BT agents require “new thinking”
Anthrax, September-October 2001The Astute Clinician: Anthrax, September-October 2001 The Astute Clinician Photo editor hospitalized in Florida, with N & V, fever, incoherent, 3 days after trip to North Carolina
CSF exam – gram positive rods
Dr. Larry Bush diagnoses anthrax, contacts public health triggering investigation and recognition of anthrax attack
22 cases, 5 deaths
Patients with unrecognized cutaneous anthrax were being treated in NY at that time
Anthrax: Potential Lethality: Anthrax: Potential Lethality “…between 130,000 and 3 million deaths could follow aerosolized release of 100 kg of anthrax spores upwind of Washington, DC area – lethality matching or exceeding that of a hydrogen bomb”
Inglesby, et al. Anthrax as a biological weapon. JAMA 1999;281:1735-45.
Anthrax – Large scale aerosolized attackKey concepts for surveillance: Anthrax – Large scale aerosolized attack Key concepts for surveillance First sign - patients presenting with non-specific “influenza-like” illness
Early recognition critical – treatment effective if given early, before classic clinical picture present
If a large release were to happen:
By the time the 1st astute clinician makes a diagnosis, many or most patients will be past the point where treatment is effective
SARS: Prototype of the Unknown?: SARS: Prototype of the Unknown? Feb. 20-25: 23 yo female at Hong Kong hotel
Mar. 1 - Admitted Tan Tock Seng Hospital, Singapore
Clinically – pneumonia, microbiologic tests negative
Treated with antibiotics and began to improve at day 9
SARS Epidemic Curve Tan Tock Seng Hospital, Singapore Feb-Mar 2003: SARS Epidemic Curve Tan Tock Seng Hospital, Singapore Feb-Mar 2003 Hsu L-Y, et. Al., Emerging Infectious Diseases 9:713;2003
http://www.cdc.gov/ncidod/EID/vol9no6/03-0264.htm
SARS Chains of transmissionSingapore: SARS Chains of transmission Singapore CDC. Severe Acute Respiratory Syndrome-Singapore, 2003 MMWR May 9, 2003 / 52(18);405-411
Effect of Travel and Missed Cases on SARS EpidemicSpread from Hotel M, Hong Kong: Effect of Travel and Missed Cases on SARS Epidemic Spread from Hotel M, Hong Kong MMWR 2003;52:241-47
SARS – Emerging infection: SARS – Emerging infection Emergence from animal reservoir
Potential for recurrence seems real
High case fatality rate, no treatment, no vaccine
Impact – human, health care, economic
Rapid global spread facilitated by:
Missed cases
International travel
Amplification in health care settings
Control difficult once established
SARS Chronology (from Utah perspective): SARS Chronology (from Utah perspective) Nov. 16 – atypical pneumonia, Guangdong Province, China
Feb. 11 – WHO notified, 305 cases, 5 deaths, Guangdong
Feb. 21 – physician from Guangdong checked into Hong Kong hotel
At least 12 guests and visitors infected
Feb 26 – Mar 5 - hotel contacts hospitalized and triggered outbreaks in Singapore, Hong Kong, Hanoi, and Toronto
March 8– an individual later arrived in Utah after travel in Hong Kong with respiratory illness
Not hospitalized until after March 15
Subsequently laboratory confirmed SARS
March 12th, 15th – WHO SARS worldwide health threat
SARSKey facts for Surveillance: SARS Key facts for Surveillance Rapid detection needed to prevent spread
Clinically nonspecific presentation
Especially difficult with background of respiratory illness
Laboratory testing helpful, but no test can reliably detect or exclude diagnosis early in course
Knowing the risk of exposure is key to diagnosis
Interaction between public health and clinicians key to recognition and control if it reemerges
What I Think It Means: Food: What I Think It Means: Food 3. Minnesota ice cream (or Costco almonds):
---delayed discovery is the rule
---importance of surveillance systems
---low level, widely spread geographic
events are “under our current radar”
---low level continual source outbreaks may be
massive
National outbreak of SE from ice cream – (continued): National outbreak of SE from ice cream – (continued) Survey of Schwan’s customers estimated
29,100 cases in MN (vs. 150 detected)
224,000 cases in U.S. (vs. 593 detected)
During peak outbreak months (Sept-Oct)
3,299 cases SE nationwide (71% increase)
Outbreak-associated cases (593) found in 41 states
Outbreak-associated confirmed Salmonella enteritidis cases, Minnesota, Sept-Oct 1994 NEJM 1996;334:1281-6: Outbreak-associated confirmed Salmonella enteritidis cases, Minnesota, Sept-Oct 1994 NEJM 1996;334:1281-6 Announcement of results October 7 Recall October 9
Surveillance:Salmonella, Ice Cream and Minnesota: Surveillance: Salmonella, Ice Cream and Minnesota Massive outbreak – widely distributed product
Difficult to detect widely distributed cases due to low level exposure above background risk
Surveillance is insensitive (cases vs. estimated disease)
Detected due to a cluster in one (lucky/good) state
Increased exposure to product
Increased testing in that region
A very active surveillance and laboratory testing program
What I Think It Means: EcoBT: What I Think It Means: EcoBT Monkeypox/Foot & Mouth Disease:
---a single event may have unpredictable
repercussions (ie, flight from Gambia)
---vectors are everywhere
---BT can equal economic terrorism
---the real concern is often long after the
exposure
Monkeypox outbreak 2003: Monkeypox outbreak 2003 Monkeypox
rare viral disease, usually West and Central Africa (African squirrels, rats, mice, rabbits)
Clinically similar to smallpox, but usually milder, much less person-to-person transmission
Outbreak May-June 2003
72 cases (37 lab-confirmed) in 6 states
Traced to exposure to prairie dogs that were caged with exotic African animals (pets)
Gambian giant-pouched rat: Gambian giant-pouched rat
Monkeypox:Risk of importation of zoonotic disease: Monkeypox: Risk of importation of zoonotic disease Monkeypox – imported 2003
Rapid detection by alert clinicians
Rapid public health response involving human, animal health agencies at local, state, federal levels
Probably prevented establishment of new disease in this hemisphere
What’s Next: EcoBT: What’s Next: EcoBT Implications of Foot and Mouth Disease:
---100 million cattle in US
---40 million pigs
No FMD in US since 1929!!!
Recent experience of countries with FMD outbreaks: UK 2001
I’m sure you’ll agree – cartoon: I’m sure you’ll agree – cartoon
What BT (probably) won’t look like:: What BT (probably) won’t look like: A single, discrete event (i.e., tornado, earthquake, plane crash)
A uniform disease (e.g., anthrax has three clearly defined clinical presentations; tularemia has six!)
A clear attack on a defined entity
What should we do? Be alert for:: What should we do? Be alert for: Groups of persons becoming ill around the same time
Sudden increase of illness in previously healthy persons
Sudden increase of the following non-specific illnesses:
a.) Pneumonia, flu-like illness, fever with atypical features
What should we do? Be alert for:: What should we do? Be alert for: b.) Bleeding disorders
c.) Unexplained rashes and mucosal or skin irritation
d.) Neuromuscular illness such as muscle weakness and paralysis
e.) Diarrhea
Simultaneous outbreaks in humans and animals populations
Temporal/geographic clustering
What I Think We Don’t Know…: What I Think We Don’t Know… The role of emergent, massive triage in BT events: exposure verses symptomatic
The importance of surge capacity in BT events that evolve over long periods
The proper construction of surveillance systems to “catch” BT outbreaks
WINSTON CHURCHILL: WINSTON CHURCHILL “Now this is not the end. It is not even the beginning of the end. But it is, perhaps, the end of the beginning.”
The “Big 8”:: The “Big 8”: 1. The six category A agents
2. SARS
3. Pandemic Influenza
What We Feel We Should Do:: What We Feel We Should Do: The critical need, “pre-event,” to designate hospitals as the “sick” hospital and the “less sick” hospital
The need to staff a committee empowered to address the above (Members?: UHA, UMA, UDOH, LHOA, DES/Governor, IHC, U of U,…) as well as the “pre-event, event and post-event” $$$ repercussions
What We Feel We Should Do: II: What We Feel We Should Do: II 3. The critical need, “pre-event” to designate
triage areas to interrupt dz transmission
A need to draft triage guidelines for the
“Big 8”
A need to address “flex” guidelines for varying case levels (eg, 10, 100, 1000)
A need to draft possible timeline guidelines for the “Big 8”