Tuberculosis Outbreak Among Hmong Refugees in the U.S. and Thailand: a Minnesota Perspective Inter-City ID Case Conference April 19, 2005

1
Tuberculosis Outbreak Among Hmong Refugees in
the U.S. and Thailand a Minnesota
PerspectiveInter-City ID Case ConferenceApril
19, 2005

• Deborah Sodt, RN, PHN, MPHManager, MDH TB
  Program

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Thanks to

• St. Paul- Ramsey County Department of Public
  Health
• Hennepin County Health Assessment and Promotion
  Clinic
• Dr. Michelle Hulse, co-chair MDH TB Advisory
  Committee
• Dr. Janet Larson, MDH TB Medical Consultant
• Regions Hospital International Clinic
• CDCs Divisions of TB Elimination and Global
  Migration and Quarantine
• MDH Refugee Health Program

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Hmong Refugees, Thailand

• Historically persecuted
• Fled Laos to Thailand 1975
• First wave of U.S. resettlement began in 1976
• Wat Tham Krabok, 2004
• Not an official refugee camp
• U.S. agreed to resettle residents on an urgent
  basis
• 15, 000 refugees slated to come to U.S.
• 52 lt 15 years old
• Anticipated high TB rates
• Higher-than-anticipated rates found

Adapted from CDC
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Timeline of Overseas Screening and U.S.
Resettlement, Hmong Refugees, 2004-2005
Overseas U.S.-based investigations CDC Enhanced
TB Screening Rec 2
Additional overseas data 17 MDR-TB Movement
halted
June 2004-January 2005 4 MDR-TB cases overseas 6
active TB cases in US (2 MDR-TB)
Movement to US, CDC Enhanced TB Screening Rec 1
Standard overseas TB screening started
Adapted from CDC
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TB Among Hmong Refugees in Thailand Objectives
of CDC Investigation

• Investigate epidemiology of TB in the camp
• Active TB case finding
• Contact tracing
• Implement appropriate control measures
• Evaluate TB screening/treatment algorithms
• Provide recommendations to camp medical staff

Adapted from CDC
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Hmong Refugees Preliminary Data (1)TB
Screening in Wat Camp

• 15,645 refugees (7,499 gt 15 years 48)
• Arrived in U.S. 9,455
• Still in Thailand 6,190
• Majority of adults had initial overseas screening
  
• Standard Protocol
• Age gt 15 years CXR, medical examination
• Under age 15 medical examination
• Sputum smears if abnormal CXR or symptoms
• CDC Enhanced TB Screening Protocol 1- June 2004
• Sputum cultures for those with abnl CXR or
  symptoms
• CXR for all gt10 years old

As of February 5, 2005
Adapted from CDC
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Hmong Refugees Preliminary Data (2)424 with
TB Class condition identified

• 351 with TB cultures performed
• 56 (16) positive TB cultures
• 17 MDR TB (30)
• 184 (52) negative TB culture results
• 111 (32) culture results pending

As of February 5, 2005
Adapted from CDC
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Hmong Refugees Preliminary Data (3)Overseas
TB Screening

• 247 active cases identified since March 2004
• 175 currently on treatment
• Estimated rates among adults
• Active 3,294/100,000 (247/7499)
• MDR 227/100,000 (17/7499)

As of February 5, 2005
Adapted from CDC
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TB Among Newly Arrived Hmong RefugeesObjectives
of Investigation in United States

• Systematically identify active TB cases
• Develop guidance for state-side evaluations
• Measure outcome of state-side evaluations
• Examine quality and performance of overseas TB
  screening algorithms

Adapted from CDC
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TB Among Newly Arrived Hmong RefugeesMethods

• Weekly TB case count from all states
• Bi-weekly conference calls with CDC, Office of
  Refugee Resettlement, TB and refugee health
  programs in affected states, Hmong National
  Development agency
• National medical issues workgroup
• Shared communications materials
• National Hmong TB case database

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TB Among Newly Arrived Hmong Refugees United
States

• 36 confirmed cases of active TB since mid-2004
• CA (26), WI (5), MN (2), 3 others (1 each)
• 4 (11) multidrug-resistant (MDRTB) (all in CA)
• 7 (19) had TB class condition Identified
  overseas
• Age
• lt 5 years 10 (28)
• 5-14 years 7 (19)
• 15 and older 19 (53)
• Additional data pending

As of March 14, 2005
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TB Among Newly Arrived Hmong RefugeesObjectives
of Investigation in Minnesota

• Identify and treat active TB cases
• Initially Refugee screening and Class B
  follow-up
• Long-term during ongoing medical care
• Timely and complete contact investigations
• Educate Hmong community, care providers and
  others
• Provide feedback to DGMQ
• Quality and performance of overseas TB screening
  algorithms
• Adequacy of communications systems

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TB Among Newly Arrived Hmong Refugees in MN
Methods

• Educational forum for clinicians
• Educational outreach to Hmong community
• Heightened surveillance at state and local levels
• Close collaboration with MDH Refugee Health
  Program
• Maintain ongoing communication with other states
  and CDC

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TB Screening in New Hmong Refugees Minnesota,
2004

• 3,318 arrived prior to January 21, 2005
• TB screening results available for 2,785 (84)
• Age
• lt 5 years 583
• age 5-14 831
• age 15 and older 1,371
• An additional 61 with TB class conditions noted
  on overseas exam were evaluated separately

As of April 5, 2005
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TB Screening in New Hmong Refugees Minnesota,
2004 Mantoux TB Skin Test (TST)
Age TST gt10 mm induration
lt 5 yrs 2.2
5-14 yrs 8.4
15 yrs 19.6
Overall 12.6
As of April 5, 2005
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TB Screening in Hmong Refugees, MN, 2004 Chest
X-RAY Results
CXR Results lt 5 yo 498 screened 5-14 yo 686 screened 15 yo 1,117 screened
Normal CXR 8 50 197
Abnormal, non-cavitary, consist w/ active TB 1 1 1
Abnormal, stable, indicative of old TB 0 0 7
Abnormal, no information given 0 0 18
Abnormal, not consistent w/active TB 0 2 45
Not done 489 (98) 633 (92) 849 (76)
As of March 11, 2005
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Active TB in New Hmong Refugees to MN Confirmed
Case 1

• 19 yo male living in Hennepin County
• Pulmonary TB
• Arrived Aug 26
• Refugee screening 32 days later identified TB
  disease
• Sputum AFB smear-neg x3, cx Mtbc
• CXR non-cavitary
• Resistant to INH, EMB, SM

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Active TB in New Hmong Refugees to MN Confirmed
Case 2

• 29 yo male living in Ramsey County
• Pulmonary TB
• Arrived Nov 19
• Abnormal CXR during refugee screening one month
  after arrival
• Cavitary CT scan 70 days after arrival
• Sputum AFB smear-neg x 6, cx Mtbc
• Sensitive to all first-line drugs

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Active TB in New Hmong Refugees to MN 4
Suspected Cases

• Age (yrs) 5, 6, 8, 67
• Hennepin, Ramsey and Olmsted counties
• Site of disease
• 2 P (sputum or gastric wash AFB smear-neg)
• 1 XP
• 1 both (sputum not obtained)
• Arrived in MN Aug (2), Sept, Nov
• Identified by refugee health assessment (3) and
  TB Class B Follow-up (1)
• days from arrival to initial TB dx 40-83

As of March 18, 2005
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TB Among Hmong Refugees Prior to 2004

• 1987-1997 9,021 primary Hmong refugees to MN
• TB screening data available for 7,168 (79)
• 764 (11) had positive TST
• 1992-2004 79 culture-confirmed Hmong TB cases
  (including secondary refugees but not including
  US-born)
• 8 (10) were MDR-TB

As of April 5, 2005
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TB Among Primary Refugee Arrivals Minnesota,
2004

• Total (all countries) 7,350
• Hmong
• 3,317 (45)
• 2 cases of active TB to date (case rate
  60.2/100,000)
• No MDR-TB
• Somali
• 2,324 (32)
• 14 cases of active TB to date (case rate
  602.4/100,000)
• One MDR-TB
• Other 1,709 (23)

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Some Recommendations

• Dont assume that overseas refugee screening
  identifies all TB disease, especially among
  children.
• Dont assume that all refugees have completed
  adequate TB screening after arriving in U.S.
• Promote screening and treatment for latent TB
  infection

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Some Recommendations

• Maintain a high level of suspicion for
  drug-resistant TB
• Make vigorous attempts to obtain specimens for
  smear and culture before starting TB treatment.
• Immediately report all suspected active TB
  disease (when in doubt, report)
• Culture positive, smear positive and/or starting
  TB medications
• Expert TB medical consultation available
• Utilize public health resources
• Directly Observed Therapy
• Free TB medications
• PH TB clinics- Hennepin, Ramsey and Olmsted
  counties

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Unanswered Questions

• Did domestic refugee screening identify all
  active TB disease (including children)?
• Why is there an apparent discrepancy between low
  rate of positive TSTs and high rate of TB
  disease?
• How many more TB cases might occur among this
  group during the next 2 years?
• Why are findings in CA so different from MN, WI,
  MI and NC?