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Primary Care Provincial TB Meeting Saskatoon, SK. October, 28, 2011 Richard Long, MD

The Determinants of Tuberculosis (TB) Transmission in the Canadian-Born Population of the Prairie Provinces (The “DTT Project”). Primary Care Provincial TB Meeting Saskatoon, SK. October, 28, 2011 Richard Long, MD.

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Primary Care Provincial TB Meeting Saskatoon, SK. October, 28, 2011 Richard Long, MD

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  1. The Determinants of Tuberculosis (TB) Transmission in the Canadian-Born Population of the Prairie Provinces(The “DTT Project”) Primary Care Provincial TB Meeting Saskatoon, SK. October, 28, 2011 Richard Long, MD

  2. Annual Age and Sex-Adjusted Tuberculosis Case Rates Per 100,000 Person-Years For Status Indians, Canadian-born ‘Others’ and Foreign-born, Canada,1989-2008

  3. The DTT Project is a: CIHR (Aboriginal Peoples Health Institute) and Health Canada (First Nations and Inuit Health Branch) co-funded, mixed-method (quantitative and qualitative) study of tuberculosis transmission on the Canadian prairies It began on April 1, 2006

  4. Scientific Team Principal Investigator: Richard Long, MD, University of Alberta Co-Investigators: Malcom King, PhD, Univ of Alberta Maria Mayan, PhD, Univ of Alberta Dennis Kunimoto, MD, Univ of Alberta Vernon Hoeppner, MD, Univ of Saskatchewan Sylvia Abonyi, PhD, Univ of Saskatchewan Pam Orr, MD, Univ of Manitoba Martha Ainslie, MD, Univ of Manitoba Dick Menzies, MD, MSc, McGill Univ Current Co-ordinators: Courtney Heffernan (Project Manager) and Kathy McMullin Database Manager: Bill Chroniaris Past-co-ordinators: Jody Boffa and Carmen Lopez

  5. How Do We Eliminate Tuberculosis? • Interrupt Transmission Altogether • All population groups but First Nations, Inuit, and Métis in particular 2. Prevent Disease in those Already Infected • All population groups but foreign-born in particular

  6. Transmission indices were significantly higher for males and Aboriginal Peoples and lower for those > 64 years of age

  7. PEDIATR INFECT DIS J 2005; 24:538-41

  8. DTT Stakeholders and Collaborating Organizations

  9. Objectives Objective 1: “To characterize the occurrence and spread of Beijing/W TB strains in Aboriginal peoples and to understand the potential role of clinical and environmental determinants of TB transmission” Objective 2: “To identify prospectively the determinants of TB transmission in the Canadian-born population, with emphasis on Aboriginal peoples”

  10. DTT Project Timeline 13

  11. Demographics, by Province, of Pulmonary TB Patients Participating in a Qualitative Interview

  12. Qualitative Studies “OLD KEYAM” - J ABORIGINAL HEALTH “THE TIPPING POINT” - SOC SCI MED “RESTORING BALANCE” - CAN J PUBLIC HEALTH ‘Potential TB Transmitters on the Canadian Prairies with and without Transmission Events; a mixed-method study” - Jessica Grant, MSc, Usask “TB in the First Nations and Métis of the Canadian Prairies versus the Maori and Pacific Islanders of New Zealand – a comparative qualitative study” - Jessica Grant, MSc, USask

  13. Major Satellite Projects - Qualitative • “Addressing TB Control in a high incidence First Nations Communities in Alberta.” Jessica Moffatt PhD (c ) Funding: - Alberta Innovates – Health Solutions (AHFMR) - PHAC - FNIHB, Alberta Region • “Tuberculosis Education in Canadian-born Aboriginal and non-Aboriginal youth: an historical, socio-cultural and public health promotional curriculum” Kathleen McMullin MEd (Project Manager) Funding: - Lung Health Program, Phase II PHAC/CLA

  14. TB on the Prairies • Between 2004 and 2008 there were 1795 cases of TB on the prairies; 640 (36.7%) in Manitoba, 492 (27.4%) in Saskatchewan and 663 (36.9%) in Alberta.

  15. Population Group and Province

  16. Age- and Sex-Adjusted Incidence of TB in Status Indians by Province, 2004-2008

  17. Age and Sex-adjusted TB incidence in Status Indians (SI) persons (on and off reserve) and foreign-born (FB) persons, relative to Canadian-born “other” persons, Prairie Provinces, 2004-2008

  18. Age-specific TB case rates per 100 000 person-years for male (M) and female (F) First Nations (FN), Canadian-born 'other' (CBO), and Foreign-born (FB) persons, Prairie Provinces, 2004-2008

  19. “Potential TB Transmitters”, Prairies 2007-2008 Between 2007 and 2008 there were 248 Canadian-born adults (age>14 years) with culture-positive pulmonary TB on the Prairies; 145 (58.5%) sputum smear-positive, 103 (41.5%) sputum smear-negative Of the ‘Potential TB Transmitters’ 89.9% were Aboriginal Peoples

  20. Canadian-born ‘Potential’ TB Transmitters by Province, Population Group, and Smear Status, Prairies, 2007-2008* SI Status IndianOA Other Aboriginal *CBO Canadian-born ‘Other’ *Other Aboriginal includes Métis, Non-Status Indians and Inuit No. of Cases

  21. Each of the 248 ‘potential TB transmitters’ diagnosed in 2007 and 2008 has a 30 month transmission window • 2007 • 2008 1 2 3 4 248 All DNA Fingerprinting was performed by NML using 12 or 24 loci MIRU-VNTR supplemented as necessary by spoligotyping. All Alberta isolates were also DNA fingerprinted with RFLP.

  22. On-Reserve Status Indian and In-Settlement MétisPotential Transmitters Prairie Provinces: North 132 (86%) South 21 (14%) North: 9 (69.2%) South: 4 (30.8%) North: 57 (89.1%) South: 7 (10.9%) North: 66 (86.8%) South: 10 (13.2%)

  23. Frequency Distribution of Canadian-born TB Transmitters on the Prairies by Sputum Smear and Community Type (2007-2008)

  24. High Prevalence (2 or more ‘potential’ transmitters in the 2007-2008 calendar years) Reserve Communities on the Prairies S: SaskatchewanM: ManitobaA: Alberta No. of Cases Community Number

  25. ‘POTENTIAL’ TB TRANSMITTERS ON THE PRAIRIES BY COMMUNITY TYPE, SMEAR STATUS AND POPULATION GROUP*

  26. LANCET 2010: Available at: www.thelancet.com DOI:10:016

  27. Indicator Result by Community Type* *All results were statistically significant at 0.05% significance (p = < 0.0001)

  28. Indicator Result by Community Type, cont’d * *All results were statistically significant at 0.05% significance (p = < 0.0001)

  29. Indicators of Well-Being in reserves with TB transmitters as compared to reserves without TB transmitters

  30. Indicators of Well-Being in high-incidence reserves as compared to reserves without TB transmitters

  31. “There appear to be three main factors necessary for the development of an epidemic (“outbreak”) of tuberculosis. These are: • a predominantly tuberculin negative population • the introduction of potent sources of infection • an environment suitable for the spread of infection” GRYZBOWSKI S. AM REV TUBERC 1957; 75: 432-41

  32. Large Reported, On-reserve Outbreaks of Tuberculosis on the Canadian Prairies, 1986-2010* CAN J INFECT DIS 1991; 2: 133-41 CAN J PUBLIC HEALTH 2004; 95: 249-55

  33. Adult (Age >14 years) Sputum Smear-positive Pulmonary TB (Source Cases) and Outbreaks of TB in Alberta (January 1, 2006 - June 30, 2008)*

  34. The convergence of factors necessary for the occurrence of an outbreak in a reserve community

  35. Chest X-ray on the Outbreak Case

  36. Cluster Cases by Population Group and Community; Outbreak Timelines

  37. Suspecting Pulmonary TB 7. Is there an upper lung zone infiltrate (cavitary or non-cavitary) on CXR; is the leucocyte count normal; is there an anemia of chronic disease? 6. Is there a high risk medical condition? 5. Has there been a failure to respond to broad spectrum antibiotics? 4. Are symptoms subacute or chronic? 3. Is there a relative absence of dyspnea? 2. Are there pulmonary symptoms (cough, sputum, hemoptysis, chest pain) in combination with constitutional symptoms (fever, night sweats, weight loss, fatigue)? Probability of TB 1. Is there an epidemiologic risk (TB contact; high risk population group)? 1 2 3 4 5 6 7 No. of Features

  38. INT J TUBERC LUNG DIS 2002; 6(4):332-339

  39. This patient is a young male Status Indian who was a close contact of a patient with infectious TB in August, 2006. A TST was positive; a CXR was normal (September, 2006). Treatment of LTBI was recommended but not completed. CXRs between March 19th and July 28th, 2007 demonstrated a progressive left upper lobe nodular process. TB was not considered until July 28th, 2007 (delay 130days).

  40. 3 2 1 4

  41. Public Health Consequences (Secondary Cases) of Smear Positive Pulmonary TB According to CXR Category and Close Contact group *Type 1 secondary cases are identified by conventional epidemiology and confirmed by molecular epidemiology; Type 2 secondary cases are identified by conventional epidemiology but are unconfirmed by molecular epidemiology (culture-negative); Type 3 secondary cases are identified by molecular epidemiology and linked to the source case spatially and temporally

  42. Public Health Consequences (TST Conversions ) of Smear Positive Pulmonary TB According to CXR Category and Close Contact group

  43. Conclusion The interruption of TB transmission in Aboriginal peoples on the Prairies is an enormous challenge; a single approach is unlikely to succeed; a multitude of well considered approaches is unlikely to succeed without greater engagement of the Aboriginal community

  44. Percent of Immigrants from Europe and Asia/Africa to Canada by Time Period (Source: Citizenship and Immigration Canada. Canadian Statistics: Immigrant Population. 05/12/03.<www.statcan.ca/english/Pgdb/demo25.htm>)

  45. Beijing/W Family of Strains in Alberta • Determined the M. tuberculosis lineage of 98.6% (n=1826/1852) of archived culture-positive isolates recovered from patients diagnosed between 1991-mid2007 • 19% (n=350) of isolates were Beijing/W lineage strains • The foreign-born contributed 94.3% of Beijing/W isolates, the vast majority (90%) being born within the Western Pacific (e.g. China, Vietnam, Korea) • Only 3.2% (n=20/632) of Canadian-born TB cases were Beijing/W strains • Only 5 Beijing/W strains among First Nations peoples • Annual incidence rates of Beijing/W strains have declined since 1994

  46. Beijing/W Family of Strains in Alberta Beijing/W strains were significantly more likely to be associated with polyresistance (a OR 3.7; 95%CI 1.3-11.11) and borderline more likely to be associated with multidrug-resistance (a OR 3.3; 95%CI 1.0-11.1) Other than these differences in drug resistance, Beijing strains appeared to present no more of a public health threat than non-Beijing strains

  47. Beijing/W Family of Strains in Alberta Beijing/W strains do not result in any more clustering or more frequent recent transmission than non-Beijing/W strains in a setting with effective TB control practices.

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