1 / 34

The New Tuberculosis (Again): The Rationale for Collaborative TB/HIV Activities

The New Tuberculosis (Again): The Rationale for Collaborative TB/HIV Activities. Kevin M De Cock MD CDC Kenya Nairobi, September 21, 2003. The New Tuberculosis (Again). Descriptive Epidemiology Interactions with HIV Transmission and Disease Interventions Future Prospects.

bernadettea
Download Presentation

The New Tuberculosis (Again): The Rationale for Collaborative TB/HIV Activities

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The New Tuberculosis (Again): The Rationale for Collaborative TB/HIV Activities Kevin M De Cock MD CDC Kenya Nairobi, September 21, 2003

  2. The New Tuberculosis (Again) • Descriptive Epidemiology • Interactions with HIV • Transmission and Disease • Interventions • Future Prospects

  3. Acknowledgements • Dr Liz Corbett, London School of Hygiene and Tropical Medicine, UK • Dr Gavin Churchyard, Anglo Gold, Welkom, South Africa • Dr Barbara Marston, CDC Kenya • Dr Doris Macharia, CDC Kenya • Dr Joseph Odhiambo, CDC Kenya • Dr Elizabeth Marum, CDC Kenya • Dr Dorothy Mbori-Ngacha, CDC Kenya • Dr Richard Chaisson, Johns Hopkins University

  4. Tuberculosis Is Not One Disease • “Old” tuberculosis (low HIV prevalence developing countries) • Tuberculosis in industrialized countries • Primary multi-drug resistant tuberculosis (former Soviet Union) • HIV-associated tuberculosis (sub-Saharan Africa, parts of Asia)

  5. The Population Dynamics of HIV-Associated Tuberculosis

  6. Interactions Between HIV and Tuberculosis • Increased relative risk for TB in HIV-infected, therefore high HIV prevalence in TB patients • TB manifestations are influenced by the severity of immune deficiency • Co-morbidity • Increased mortality • Increased recurrence

  7. Trends in Tuberculosis Case Notification Rates (per 100,000) in South African Goldminers

  8. 1991-4 1995-7 1998-9 99-2000 Age-specific, HIV-Negative Tuberculosis Incidence Rates, South African Gold Mines, 1991-2000.

  9. Trends in Tuberculosis in South African Goldminers, 1991-2000 • Overall tuberculosis incidence has increased four-fold to >4000/100,000 per year • Age, silicosis, and HIV were independent risk factors for tuberculosis • In HIV-negative persons, age-specific tuberculosis incidence did not change significantly • A strong, DOTS-based programme contained tuberculosis incidence in HIV-negative persons • Interpretation of tuberculosis trends requires stratification by HIV status (Corbett et al, 2003)

  10. Tuberculosis Trends in Abidjan, 1981-1991

  11. Tuberculosis Epidemiology • Incidence - new cases/population/time (eg n cases TB/100,000/year) • Prevalence – cases/population (eg n cases HIV/100) • Prevalence = incidence x duration • Tuberculosis transmission is predominantly from persons with smear-positive disease

  12. Incidence, Prevalence, and Duration of Smear-Positive Tuberculosis in South African Goldminers HIV-Pos HIV-Neg Ratio Incidence 2869 497 6.0 (per 105/yr) Prevalence 0.44 0.55 0.8 (%) Mean 0.15 1.15 0.13 duration (years) (Corbett et al, 2003)

  13. Proportional Distribution by HIV Status of Smear-Positive Tuberculosis Incidence and Duration in South African Goldminers

  14. Tuberculosis Transmission and Disease in Relation to HIV In high HIV prevalence settings: • Most tuberculosis disease occurs in HIV-positive persons • Much or most tuberculosis transmission is from HIV-negative persons

  15. Requirements for Tuberculosis Control in the Era of HIV/AIDS • Effective treatment of active cases to reduce transmission of Mycobacterium tuberculosis • Effective HIV prevention • Reduction in vulnerability to TB of HIV-infected - Preventive therapy - Highly active antiretroviral therapy

  16. Treatment of HIV-Associated Tuberculosis • Acceptable “cure” rates with rifampin-based Rx • Mortality 3-4x increased; highest in first month • HAART reduces mortality (3/85 [3.5%] vs. 13/103 [12.6%], RR 0.28 [0.08-0.95]) (AIDS 2002;16:75) • 549 in Spain with EPTB TB as 1st AIDS dx: (Barcelona 2002 ThPeC7459)

  17. Challenges Drug interactions Pill burden Drug toxicity Adherence Monitoring Immune reconstitution Supervision and care delivery, cost Approaches Delay ARVs till rifampicin completed Efavirenz if early Rx essential Clinical monitoring HAART in Patients with Tuberculosis – Practical and Clinical Considerations

  18. Impact of HAART on TB Risk

  19. HIV-Related TB Associated with HAART in Rio de Janeiro TB/HIV Cases 1995 – 159 cases 1996 – 148 cases 1997 – 105 cases 1998 – 100 cases 1999 – 42 cases Source: Mello et al 2000.

  20. Impact of HAART on Tuberculosis Incidence--Summary • HAART reduces risk of TB by about 80% • TB incidence remains higher than in HIV-negative • Numbers of cases averted depend on incidence of TB, stage of HIV, treatment effectiveness (adherence etc) • Potential exists for TB and HIV drug resistance • Potential exists for worsening of TB incidence

  21. The Need to Scale Up HIV Testing • UN Declaration of Commitment (UNGASS 2001): - 20% reduction in MCT by 2005 - 50% reduction in MCT by 2010 • Almost 40 million women become pregnant annually in sub-Saharan Africa • 3 million HIV-infected persons to receive HAART by 2005 (WHO) • 175 million globally require HIV testing (WHO, 2002)

  22. Rapid Testing for HIV • Two different, rapid, simple whole blood tests are used for every client • Done on site by trained Counselor • Confirmed results in 15 to 20 minutes • Tests used in Kenya: • Abbott Determine • Trinity Biotech UniGold

  23. Tuberculosis and HIV, 2003 Persons positive for one of these diseases should be tested for the other

  24. Expectations of Tuberculosis Programs in the HIV/AIDS Treatment Era • Aim to reduce transmission, disease, death • Provide TB treatment in the context of AIDS care to HIV-positives • Provide TB treatment to HIV-negatives • Decentralize provision of services • Define responsibilities and functioning of TB and HIV/AIDS care programs

  25. Models of TB Program Functioning in the HAART Era • Limit TB Program Responsibilities - Policy - Quality control - Care of HIV-negative TB only - Registration and outcome evaluation 2. Provide all necessary care, including TB, HAART, and OI prophylaxis

  26. Should TB Programs Administer HAART? • Pro— • Probably best equipped to manage HAART (experience with long term follow-up, adherence, monitoring) • Overlapping populations • Clinical considerations • Con — • HAART would overwhelm most TB programs • Infection control • Drug interactions

  27. Interventions for Effective Tuberculosis Control in the Era of HIV • Widespread HIV testing • Analysis of TB trends by HIV status • DOTS expansion • Active case finding (household contacts, HIV-positive persons) • Preventive therapy in HIV-infected • HAART in HIV-infected

More Related