340 likes | 554 Views
REFLECTIONS ON HIV/AIDS AND MDR. PAHO/WHO. Dr. Andrea Luna Heine Resident/Consultant, USAID/PAHO Training Program SupraNational Reference Laboratory, Chile. 1. Current Situation 2. Evidence Found: Conclusive? 3. Getting Closer to an Answer. 1. Current Situation.
E N D
REFLECTIONS ON HIV/AIDS AND MDR PAHO/WHO Dr. Andrea Luna Heine Resident/Consultant, USAID/PAHO Training Program SupraNational Reference Laboratory, Chile
1. Current Situation 2. Evidence Found: Conclusive? 3. Getting Closer to an Answer Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
1. Current Situation Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Estimated Total Population Living with HIV/AIDS (end of 2001) Eastern Europe and Central Asia 1 million Western Europe 560,000 North America 940,000 East Asia and Pacific 1 million North Africa and Mideast 440,000 Central America 420,000 South East Asia 6.1 million South America 1.4 million Sub-Saharan Africa 28.1 million Australia 15,000 Total: 40 million
per 100,000 pop. < 10 10–24 25–49 50–99 100–299 300+ No estimate The highest estimated rates for TB are found in Africa Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Growing Tendency of TB Incidence (African and Eastern European Countries) 200 180 Africa, low HIV Africa, high HIV 160 Post-communist countries 140 120 Notification Rates per 100,000 100 80 60 40 20 0 1980 1985 1990 1995 2000 Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Estimated Distribution of Adults Infected with HIV and Tuberculosis, 2000 100,000 50,000 50,000 400,000 150,000 South East Asia 2.3 million Sub-Saharan Africa 9.5 million 450,000 5,000 Global Total : 13 million Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
In Africa, more HIV means more TB; however, the MDR rate is relatively low. Zimbabwe MDR=1.9% Malawi MDR=0.3% Kenya MDR=0.5% Tanzania MDR=0.9% Ivory Coast MDR=5.3% Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Impact of HIV on Tuberculosis(USA, 1980–1992) Cases (thousands) 35 30 observed 25 57,000 more cases 20 15 foreseen 10 5 0 79 80 81 82 83 84 85 86 87 87 88 89 90 91 92 93 Year Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
0 - 0.9 1 - 2.9 3 - 4.9 5 - 6.9 7 + No estimate Estimated Percentage of MDR among New TB Cases, 2000 Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Prevalence of HIV Infectionamong TB Patients (Selected Countries, Region of the Americas, 2001) NY 199726% English Caribbean (2000)*: BAH 38% BEL 14% GUY 32.4% JAM 16% SUR 14% TRT 32% DOR 1997 17% HON 20018.0% MEX 1990-1994 3.1% GUT20008.0% ELS 19962.8% NIC1999 0.8% Rio de Janeiro BRA1995-199835.6% Sources: Reports from National TB-Control Programs. * Caribbean Epidemiology Centre (CAREC). ARG 1995 2.2% URU19970.7% Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Prevalence of MDRamong Cases Never Treated(Region of the Americas, 1994–2002) CAN 1.2% - USA 1.2% DOR 6.6% CUB 0.3% MEX: 3 states 2.4% Puerto Rico 2.5% GUT 0.7% VEN 0.3% HON 1.8% ELS 0.3% NIC 1.2% COL 1.47% ECU 6.6% BRA 0.9% PER BOL 3.0% 1.2% No data >= 3% - CHI ARG 0.6% < 3% - 0.9% URU =< 1% - 0.01% Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
2. Evidence Found: Contradictory? Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Is there any association between HIV and TB/MDR ? % of resistance to one or more drugs Gordin 1996 Bercion 1995 Ash 1996 Dosso 1999 Spellman 1997 Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Are hospitals a risk factor for HIV ? 10 Odds Ratio (95%CL) 1 0.1 Espinal 2001 Yoshiyama Kenyon 1999 Kenyon 1999 2001 Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
How reliable are the publications on this?Certain methodological errors crop up frequently. Non-representative samples • Samples not randomized. • Methodological defects in sample design (descriptive estimates, small size) • Subproducts (Designed with other objectives in mind.)
How reliable are the publications on this? Certain methodological errors crop up frequently. Biases • Information Bias • Fails to report previous treatment. • Fails to report contacts (MDR). • Memory Bias • Fails to remember medication given (incorrectly reported as 'never treated'). • Selection Bias • Serious or uncompensated percentages. • Hospital reports. • Informed consent.
How reliable are the publications on this? Certain methodological errors crop up frequently. Factors Creating Confusion • No DOTS • Flexibility in observed treatment. • Irregularity in treatment. • Exposure to MDR Strains • Less time in hospitals with a greater probability of MDR contact.
How reliable are the publications on this? Certain methodological errors crop up frequently. • Non-TB micobacteria • Late diagnosis Diagnosis Existence of outbreaks? • Differentiated behavior • Outbreaks? • Can become generalized among the general population (Cluster: RFLP)
HIV/AIDS High Prevalence of MDR Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Lack of Control in the DOTS Strategy HIV/AIDS High Prevalence of MDR Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
MDR in New York(1992–2000) Source: New York City Department of Health. Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
3. Coming closer to an answer ... Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Initial Resistance Study (Chile, 2001) • Samples input 939 (737) • Samples useful for evaluation 867 • Discarded samples 70 (7.5%) • 3.2 % due to false report of 'never treated' (30) • 1.4 % due to non-TB micobacteria (13) • 2.9% for technical reasons (19 with no data y 8 contaminated) Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Verifying the Information • Initial survey. • Cross-referencing national TB databases. • ENO (EX-RMC14) Epidemiology • Registered monthly lab cases ISP • Dynamic monthly RNTBC Nursing • Review of 100% of the files with >= 1 resistance. • Review of a variable percentage of files from sensitive patients x health service from 20% to 100%. • Cross-referencing CONASIDA data on HIV/AIDS. Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Trends of Initial and Acquired Resistance: Global-Resistance and Multi-Resistance Forms (1971–2001) GlobalInitialResistance AcquiredInitialResistance InitialMulti-Resistance AcquiredMulti-Resistance Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
General Characteristics Analysis of the Impact of HIV/AIDS and the Immigrant Population • There is no difference in the characterization of the population as regards sex and age among the resistant and non-resistant population. • The population profile is not affected by populations with HIV/AIDS and migrants; but this is the case if there is change within these populations vis-à-vis the national population. Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
General Characteristics Analysis of the Impact of HIV/AIDS and the Immigrant Population • The population co-infected with HIV/AIDS in this sample was 3.4%. • Neither of the two subpopulations affects the national resistance profile. Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
Sample Characterization • Regarding HIV/AIDS • Patients with HIV/AIDS: 3.3% of all 'never-treated' TB cases. • Average age, 37.2 MD 37, 80% of the population is male. • 1.1% of the patients are MDR (0.7 national MDR). • Regarding being an immigrant • Foreign patients = 2.3% of TB cases 'never treated'. • Average age, 33.5 MD 29.5; 60% are women. • 1.1% of the patients are MDR. Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
What Other Chilean Studies Show • HIV patients act as an outbreak. • 2.4% are MDR among 'never treated' (‘naive’) TB-HIV/AIDS patients (national estimate: 0.7%) • 19.8% are MDR among previously treated TB-HIV/AIDS patients (national estimate: 20%) Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003
HIV/AIDS TB MDR
HIV/AIDS TB Micobacteria? Misreported as ‘never treated’? MDR TB DOTS? Outbreak?
Summing UpHIV/AIDS and MDR TB … • The global evidence available (Africa, USA, etc.), as well as Regional experiences (Chile), do not indicate any causal association. • HIV, however, can be a factor interacting in the generation of MDR TB, above all in the presence of poor tuberculosis control and insufficient biosafety measures. • The lack of compliance with strictly supervised anti-TB treatment, as well as exposure to other MDR TB patients, constitute risk factors for drug resistance among this population group. Workshop on TB/HIV Co-Infection, San Pedro Sula, Honduras, August 2003