Transcript Changes to CDC protocol for flight-related tuberculosis

CDC 2011 Protocol for
Flight-Related
Tuberculosis Contact Investigations
Karen J Marienau, MD, MPH
Centers for Disease Control and Prevention
[email protected]
TB PEN Webinar
Aug 7, 2013
National Center for Emerging and Zoonotic Infectious Diseases
Division of Global Migration and Quarantine
Overview
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Background of flight-related tuberculosis (TB) contact
investigations (CIs)
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Changes to CDC protocol for flight-related tuberculosis
contact investigations (TBCIs) that were implemented in
July 2011

Preliminary results of TBCIs conducted under the CDC
2011 protocol in comparison to those conducted under
the CDC 2008 protocol
Background
Airline TBCIs
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World Health Organization (WHO) provided guidelines
for flight-related TBCIs in 2006 (updated in 2008*)

Public health benefits of airline TBCIs are not
well established

Airline TBCIs are time-consuming, costly, and compete
for resources with other TB prevention and control
efforts with well-established benefits
*http://www.who.int/tb/publications/2008/WHO_HTM_TB_2008.399_eng.pdf
Background
Airline TBCIs (cont.)
 Two of 13 studiesa showed reliable evidence of
Mycobacterium tuberculosis transmission
 Two CDC reviewsb,c of TB CIs conducted in the US were
inconclusive, but suggested risk of transmission was low
 No documented cases have been reported of TB disease
resulting from exposure during air travel
aAbubakar, I. Tuberculosis
and air travel: a systematic review and analysis of policy. Lancet
Infect Dis. 2010:10:176-83
bKornylo-Duong
K,, et al. Three air travel-related contact investigations associated with
infectious tuberculosis, 2007–2008. Travel Med Infect Dis (2010);8:120-8
cMarienau
KJ, et al. Tuberculosis investigations associated with air travel: US CDC Jan 2007June2008. Travel Med Infect Dis (2010);8:104-12
Flight-related TBCIs in the United States
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Quarantine branch staff
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Determine whether the case meets protocol criteria
for conducting a TBCI
Obtain passenger contact information from airline
and Customs and Border Protection
Provide information to US state health departments
US health departments

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Locate and evaluate passenger contacts according to
national guidelines*
Report results to DGMQ (voluntary)
*Guidelines for the Investigation of Contacts of Persons with Infectious Tuberculosis:
Recommendations from the National Tuberculosis Controllers Association and CDC
MMWR 2005; 54 (No. RR-15, 1-37)
Comparative Cost-Benefit Analysis
To evaluate the cost-benefit of TBCIs for
preventing TB disease following exposure
during air travel we:

Identified 3 potential alternatives to the CDC 2008
protocol for flight TBCI

Selected one potential alternative protocol to the
2008 CDC protocol for comparative risk and economic
analyses
Comparative Cost-Benefit Analysis
CDC 2008 Protocol vs. CDC 2011 Protocol

Risk analyses:
 Epidemiology of TBCIs conducted from 2007 to 2009 to predict
numbers and clinical characteristics of index cases and number of
passenger contacts
 Outcomes data from TBCIs from Jan 2007 to Jun 2008* to predict
passenger contact outcomes
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Economic analyses:
 Estimate the immediate costs of TBCIs for health department and
DGMQ
 Return on Investment Model to estimate the long-term impact of
airline TBCIs related to reducing future cases of TB disease:
(Gain of investment – Cost of investment) / (Cost of investment)
*Marienau KJ, Burgess GW, Cramer EH, et al. Tuberculosis Investigations associated with air
travel: US CDC Jan 2007-June2008. Travel Med Infect Dis 2010;8:104-12
Comparison of 2008 and 2011CDC TB Protocols for
Flight-Related Tuberculosis Contact Investigations
Criteria
2008 CDC Protocol
2011CDC Protocol
Diagnosis relative to
flight date
Within 3 months of flight
Within 3 months of flight
Time since flight
when CDC notified
Within 6 months of flight
Within 3 months of flight
Isolate:
susceptible to isoniazid (INH)
or rifampin (RIF)
Sputum smear +, chest
Sputum smear +
radiograph (CXR)
AND
with/without cavitation; OR CXR with cavitation
sputum smear - and CXR
with cavitation
Isolate:
multidrug-resistant (resistant
to INH and RIF)
All
All
Results of Comparative Risk and Economic
Analyses for CDC 2008 and 2011 Protocols
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Risk of acquiring latent TB infection (LTBI) on a flight:
2008 vs. 2011 criteria
 2008 criteria: risk range was 1.1% - 24%
 2011 criteria: risk range was 1.4% - 19%
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Economic impact– Immediate
 2011 protocol would result in about half as many TBCIs,
and approximately 50% reduction in HD costs
Economic impact – Long term
 Return on investment comparable for the two protocols
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Risk and Economic Analyses Outcomes
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Our analyses predicted that public health resources
would be conserved with minimal negative effect on TB
prevention and control if the 2008 CDC flight-related
TBCI protocol was replaced by the 2011 CDC Protocol

The 2011 CDC protocol was implemented July 1, 2011,
with endorsement by CDC’s Division of TB Elimination
and the National TB Controllers Association
2011 CDC TB Air Travel Protocol
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
Implemented July 1, 2011
Criteria for initiating a TBCI
 Index case
• diagnosed ≤ 3months after flight
• Sputum smear positive AND cavitation on CXR OR
• Multidrug-resistant isolate
 Flight
• ≥ 8 hours long (gate-to-gate)
• ≤3 months of notification of index case to CDC
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Considerations for doing a CI even if criteria not met
 Cavitation on CT scan but not on CXR, or no CXR
 More than expected close household contacts with
positive screening tests
 Laryngeal TB
Comparison: 2008 Protocol Last 18 months and
2011 Protocol First18 Months
Numbers
Jan 1, 2010-June 30,
2011* (2008 Protocol)
July 1, 2011-Dec. 31,
2012 (2011 Protocol)
TB Cases
119*
52
Passenger contacts
(total)
3798*
1620
2790*
1096
Passenger contacts
(Assigned to US health
departments)
*Excludes 5 cases, 51 flights, and 1549 passengers (911 passengers assigned to states)
from contact investigations done for outbound flights because DGMQ stopped doing
CIs on outbound flights in May 2011. Since then DGMQ notifies the country where flight
arrived of the TB case, and they conduct a CI according to their national policy .
Preliminary data
Acknowledgments
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State and local TB control program staff
National TB Controllers
DTBE: Ken Castro, Tom Navin, Phil Lobue, Maryam Haddad,
Sundari Mase, John Jereb
CDC Quarantine Station staff involved in TBCIs
Quarantine Branch staff involved in risk and economic
analyses of 2011 protocol:
 Elaine Cramer, Maggie Coleman, Nina Marano, Marty Cetron
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Quarantine Branch staff that assisted with data
entry/analyses
 Chris Schembri , Jenna Kirschenman, and Faith Washburn
QUESTIONS?
THANK YOU!
The findings and conclusions in this presentation are those of the authors and do
not necessarily represent the official position of the
Centers for Disease Control and Prevention
National Center for Emerging and Zoonotic Infectious Diseases
Division of Global Migration and Quarantine