Emerging Infectious Disease Threats in Theatre: Risk and Mitigation Institute of Federal Health Care

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Emerging Infectious Disease Threats in Theatre
Risk and MitigationInstitute of Federal Health
Care Roundtable
Examples of Emerging Infectious Disease Threats
from the Clinicians Vantage Point

• COL Naomi Aronson
• Director, Infectious Diseases Division
• Department of Medicine
• Uniformed Services University of the Health
  Sciences, Bethesda MD

The views expressed in this session are those of
the author and do not reflect the official policy
or position of the Department of the Army,
Department of Defense, or the U.S. Government
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Emerging Infectious Diseases in Theatre
Emphasis on Afghanistan

• Infectious diseases that are unusual for US
  practitioners to manage
• - Leishmaniasis, visceral and
  cutaneous
• - Malaria
• - Q fever
• Antimicrobial resistant pathogens
• - Multidrug resistant gram negative
  bacteria
• - Multidrug resistant tuberculosis
• Undifferentiated febrile illness with limited
  diagnostic capability in theatre

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Leishmaniasis

• Visceral Leishmaniasis
• - L. donovani in Afghanistan vs L.
  infantum in Iraq
• - Symptom onset may be after leaving
  theatre
• Asymptomatic and subclinical
  infection more common
• Later reactivation during
  immunocompromising conditions
• - Rapid diagnostic test rk39
• - Treatment is expensive IV Ambisome
• - Transfusion related transmission
  possible

• Kala azar Detect
• FDA cleared
• gt95 sensitivity
• Uses serum
• 10 cross reaction with
• cutaneous leishmaniasis

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Leishmaniasis

• Cutaneous Leishmaniasis
• - L. major and L. tropica in Afghanistan
• - L. tropica
• less likely to self heal, risk for
  late reactivation
• ? risk for viscerotropic, mucosal
  involvement
• no rapid speciation tool (WRAIR PCR
  not optimized for species)
• treatment is more difficult

Dowlati Clin Dermatol 1996. 14425-31
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Malaria

• Risk in Afghanistan
• - P. vivax and P. falciparum
• - Challenges in prophylaxis (daily, GI
  upset, hypnozooites)
• - P. vivax with late presentation, post
  redeployment
• - Rapid diagnostic test
• - Treatment newly approved CoArtem,
  will it be fielded?
• - Blood supply

• For P. vivax and parasitemiagt5,000 per µl
• - Sensitivity 93.5
• - Specificity 99.8
• For P. falciparum and parasitemiagt5,000 per µl
• - Sensitivity 99.7
• - Specificity 94.2

Kolaczinski J. Lancet. 2005. 3561507
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Q Fever

• Caused by bacteria Coxiella burnetti
• Flu-like febrile syndrome, pneumonia, hepatitis
• - less commonly
• meningoencephalitis, cholecystitis, orchitis,
  peri/myocarditis
• - most commonly subclinical, self
  limited
• Chronic Q fever about 1 cases
• - associated with cardiac valve
  abnormalities
• - associated with immunosuppression,
  including pregnancy

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Diagnosis and Treatment Q Fever

• FDA approved serology is IFA based
• - Phase II antibodies elevated in acute
  infection
• - Phase I antibodies elevated in
  chronic infection
• Results vary depending on assay
• - Focus Diagnostics (Send out, Quest
  Laboratory) IFA
• - USAFSAM IFA (uses Focus Diagnostics
  kit)
• - DoD Veterinary Laboratory (not for
  human diagnosis)
• - JBAIDS PCR (not FDA cleared)
• - CDC IFA
• - USAMRIID ELISA
• Treatment
• - Acute infection doxycycline for 21
  days
• - Chronic infection
• doxycycline and hydroxychloroquine
  for 18 months

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Emerging Issues with Q fever

• What is the risk?
• - How to prevent?
• Diagnostics
• How to stratify those needing more aggressive
  treatment?
• How to identify those with chronic infection?
• - Endocarditis
• Chronic sequelae
• - Chronic fatigue syndrome

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Multidrug Resistant Gram Negative Bacteria

• Acinetobacter baumanii, ESBL producing
  Klebsiella,
• E. coli, Pseudomonas
• Issue is infection control
• - In theatre MTF
• - During transfer
• - CONUS military and
  civilian
• - Occupational transmission
• - Nosocomial transmission to
  more vulnerable patients
• Running out of effective antibiotics
• - Colistin (respiratory, CNS
  penetration)

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Wortmann G. ICHE. 2008. 29(6)553-5
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Tuberculosis

• Afghanistan has 12th highest per capita rate of
  TB in world
• - 3 new cases are MDR TB, 36 prior Rx
  cases (2007)
• - Category 1 regimen is 2 (HR)ZE/6(HE)
  (WHO)
• - National Reference Lab
• US medical facilities in theatre send AFB culture
  to LRMC
• - Significant turnaround time, AFB
  culture capacity not intrinsic
• - Opportunity to partner with CDC for
  rapid resistance testing (72 hr )
• none of current rapid tests
  are FDA approved assays
• How are potentially exposed MDR TB contacts
  followed, LTBI managed?
• Late reactivating disease may have downstream
  impact US

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Undifferentiated Febrile Illness

• Limited diagnostic capability in theater
• - Examples of endemic diseases with
  possible chronic sequelae
• Brucellosis
• Typhoid Fever/ non typhoidal
  Salmonellosis
• - Emerging or possible Viral Infections-
  how could they be detected?
• Sand Fly Fever
• Dengue
• Chikingunya
• Novel Influenza
• Control of new diseases in and out of theatre as
  troops deploy