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M C Raviglione

Publications and source records attributed to M C Raviglione.

At least 19 recordsLinked to original sources
PubMed2004

Tuberculosis in HIV-infected persons in the context of wide availability of highly active antiretroviral therapy.

Highly active antiretroviral therapy (HAART) greatly reduces the risk of developing tuberculosis for HIV-infected persons. Nonetheless, HIV-associated tuberculosis continues to occur in countries where HAART is widely used. To identify the characteristics of HIV-infected persons who develop tuberculosis in the context of the availability of HAART, the current authors analysed data taken from 271 patients diagnosed, in Italy, during 1999-2000. These patients represent 0.7% of the 40,413 HIV-infected patients cared for in the clinical units participating in this current study. From the data it was observed that 20 patients (7.4%) had a previous episode of tuberculosis whose treatment was not completed. Eighty-one patients (29.9%) were diagnosed with HIV at tuberculosis diagnosis, 108 (39.8%) were aware of their HIV status but were not on antiretroviral treatment and 82 (30.3%) were on antiretroviral treatment. Patients on antiretroviral treatment were significantly less immunosuppressed than patients with HIV diagnosed concurrently with tuberculosis, or other patients not on antiretrovirals (median CD4 lymphocytes count: 220 cells x mm(-3) versus 100 cells x mm(-3), and 109 cells x mm(-3), respectively). No significant differences in clinical presentation of tuberculosis according to antiretroviral therapy status were recorded. Failure of tuberculosis control interventions (e.g. noncompletion of treatment) and of HIV care (delayed diagnosis of HIV infection and suboptimal uptake of therapy) may contribute to continuing occurrence of HIV-associated tuberculosis in a country where highly active antiretroviral therapy is largely available. However, a significant proportion of cases occur in patients who are on antiretroviral treatment.

AIDS-Related Opportunistic Infections↗
PubMed2004

DOTS expansion: will we reach the 2005 targets?

The global targets for tuberculosis control consist of detecting 70% of estimated infectious cases and curing 85% of these by 2005. Since the introduction of the DOTS strategy, DOTS geographical coverage has increased substantially and treatment success rates under DOTS are approaching the targets, standing at 82% in 2000. However, DOTS case detection, albeit increasing, is still relatively low, at 32% in 2001. This target may not be reached by 2005. The low case detection is unlikely to stem from overestimating the global number of TB cases which has been estimated on several occasions, but from TB cases not being detected or notified for various reasons. The population may have poor access to TB services, cases may not be suspected or correctly diagnosed, cases may not be notified, and/or public health programmes or the private sector may not be adequately linked to the National Tuberculosis Programmes. Since the global TB targets were set, progress has been made. Political commitment has increased, additional financial resources mobilised, access to anti-tuberculosis drugs augmented and planning and coordination improved. Constraints still remain, the most important related to human resource capacity. Although the issue is being tackled, many countries still suffer from a lack of trained health care professionals. Finally, new strategies have been developed to face the current challenges such as public-private mix, community TB care, social mobilisation, TB/HIV collaborative interventions and Practical Approach to Lung Health. The current efforts should be maintained and strengthened in order to approach these targets.

Antitubercular Agents↗
PubMed2002

Evolution of WHO policies for tuberculosis control, 1948-2001.

We examine the evolution of WHO managerial policies for tuberculosis control during 1948-2001 to provide a new framework that will accelerate control expansion in the near future. In the first period (1948-63), a vertical approach to tuberculosis control was the policy adopted by WHO and the international community. However, although this approach was successful in more-developed countries, it largely failed in resource-poor settings. As a result, involvement of general health services was soon deemed essential. During 1989-98, a new framework for effective tuberculosis control was created and a new five-element strategy was branded with the name of DOTS. This period was characterised by the recognition of tuberculosis control as a public-health priority, the intensification of tuberculosis control efforts worldwide, and the return of tuberculosis to the political agenda of governments. However, although nominal adoption of DOTS increased rapidly due to massive promotion by WHO and partners, expansion to provide full access was too slow and only 23% of all infectious cases in 1999 were managed under DOTS. A truly multisectoral approach based on advocacy and social mobilisation, community involvement, and engagement of private-for-profit practitioners is becoming the way forward for tuberculosis control. HIV-associated tuberculosis and multidrug-resistant tuberculosis must be tackled as priority issues. We conclude that, based on the lessons of the past, the future of tuberculosis control should be focused on a pragmatic approach combining a specialised, well-defined management system with a fully integrated service delivery. A multisectoral approach that builds on global and national partnerships is the key to future tuberculosis control.

AIDS-Related Opportunistic Infections↗
PubMed2002

European framework for tuberculosis control and elimination in countries with a low incidence. Recommendations of the World Health Organization (WHO), International Union Against Tuberculosis and Lung Disease (IUATLD) and Royal Netherlands Tuberculosis Association (KNCV) Working Group.

As countries approach the elimination phase of tuberculosis, specific problems and challenges emerge, due to the steadily declining incidence in the native population, the gradually increasing importance of the importation of latent tuberculosis infection and tuberculosis from other countries and the emergence of groups at particularly high risk of tuberculosis. Therefore, a Working Group of the World Health Organization (WHO), the International Union Against Tuberculosis and Lung Disease (IUATLD) and the Royal Netherlands Tuberculosis Association (KNCV) have developed a new framework for low incidence countries based on concepts and definitions consistent with those of previous recommendations from WHO/IUATLD Working Groups. In low-incidence countries, a broader spectrum of interventions is available and feasible, including: 1) a general approach to tuberculosis which ensures rapid detection and treatment of all the cases and prevention of unnecessary deaths; 2) an overall control strategy aimed at reducing the incidence of tuberculosis infection (risk-group management and prevention of transmission of infection in institutional settings) and 3) a tuberculosis elimination strategy aimed at reducing the prevalence of tuberculosis infection (outbreak management and provision of preventive therapy for specified groups and individuals). Government and private sector commitment towards elimination, effective case detection among symptomatic individuals together with active case finding in special groups, standard treatment of disease and infection, access to tuberculosis diagnostic and treatment services, prevention (e.g. through screening and bacille Calmette-Guéria immunization in specified groups), surveillance and treatment outcome monitoring are prerequisites to implementing the policy package recommended in this new framework document.

Communicable Disease Control↗
PubMed2002

Frequency of recurrence among MDR-tB cases 'successfully' treated with standardised short-course chemotherapy.

SETTING: Ivanovo Oblast, Russian Federation, 300 km north-east of Moscow, where a pilot DOTS TB control programme was implemented in October 1995. OBJECTIVE: To determine the frequency of TB recurrence among MDR (multidrug-resistant) patients who achieved treatment 'success' on standard short-course chemotherapy. METHODS: All patients with MDR tuberculosis, defined as resistance to at least isoniazid and rifampicin, who were declared 'cured' or 'treatment completed', were identified using the district register and traced whenever possible. Eligible patients underwent medical examination and, if necessary, chest radiography, sputum smear examination, culture and susceptibility testing. If the patient had died, the relatives were interviewed to try to determine the reasons for death. RESULTS: Of 18 patients eligible for analysis, five (27.8%) were documented to have recurrence (two of seven patients resistant to HRSE, one of five patients resistant to HRS and two of six patients resistant to HR). Patients receiving the Category I regimen were more likely to relapse than those receiving the Category II regimen (40% vs. 12.5%). The median time to relapse was 8 months; 2.46 recurrences were observed in 100 person-months (3.17 in category I and 1.3 in Category II patients). CONCLUSIONS: The frequency of TB recurrence among MDR-TB patients declared 'cured' after short-course chemotherapy is high. Improvements in treatment success, after removal of programme-related pitfalls in the treatment delivery process, must incorporate methods for early detection of MDR, along with adequate treatment regimens including second-line drugs. Culture-based bacteriological confirmation at the end of treatment is recommended.

Adult↗
PubMed2001

Global trends in resistance to antituberculosis drugs. World Health Organization-International Union against Tuberculosis and Lung Disease Working Group on Anti-Tuberculosis Drug Resistance Surveillance.

BACKGROUND: Data on global trends in resistance to antituberculosis drugs are lacking. METHODS: We expanded the survey conducted by the World Health Organization and the International Union against Tuberculosis and Lung Disease to assess trends in resistance to antituberculosis drugs in countries on six continents. We obtained data using standard protocols from ongoing surveillance or from surveys of representative samples of all patients with tuberculosis. The standard sampling techniques distinguished between new and previously treated patients, and laboratory performance was checked by means of an international program of quality assurance. RESULTS: Between 1996 and 1999, patients in 58 geographic sites were surveyed; 28 sites provided data for at least two years. For patients with newly diagnosed tuberculosis, the frequency of resistance to at least one antituberculosis drug ranged from 1.7 percent in Uruguay to 36.9 percent in Estonia (median, 10.7 percent). The prevalence increased in Estonia, from 28.2 percent in 1994 to 36.9 percent in 1998 (P=0.01), and in Denmark, from 9.9 percent in 1995 to 13.1 percent in 1998 (P=0.04). The median prevalence of multidrug resistance among new cases of tuberculosis was only 1.0 percent, but the prevalence was much higherin Estonia (14.1 percent), Henan Province in China (10.8 percent), Latvia (9.0 percent), the Russian oblasts of Ivanovo (9.0 percent) and Tomsk (6.5 percent), Iran (5.0 percent), and Zhejiang Province in China (4.5 percent). There were significant decreases in multidrug resistance in France and the United States. In Estonia, the prevalence in all cases increased from 11.7 percent in 1994 to 18.1 percent in 1998 (P<0.001). CONCLUSIONS: Multidrug-resistant tuberculosis continues to be a serious problem, particularly among some countries of eastern Europe. Our survey also identified areas with a high prevalence of multidrug-resistant tuberculosis in such countries as China and Iran.

Antitubercular Agents↗
PubMed2001

The burden of drug-resistant tuberculosis and mechanisms for its control.

Drug resistance in tuberculosis is largely a man-made phenomenon caused by erroneous prescribing practices on the part of physicians and noncompliance on the part of patients. The global epidemiology of drug-resistant TB, the impact of standardized short-course chemotherapy (SSC), and the potential future evolution of MDR TB are discussed in this chapter.

Animals↗
PubMed2001

Determinants of drug-resistant tuberculosis: analysis of 11 countries.

SETTING: Eleven countries/territories. OBJECTIVES: Global information on the determinants of drug-resistant tuberculosis (TB) based on representative data is not available. We therefore studied the relationship between demographic characteristics, prior TB treatment, and human immunodeficiency virus (HIV) infection with anti-tuberculosis drug resistance. METHODS: Population-based representative data on new and previously treated patients with TB collected within an international drug resistance surveillance network. RESULTS: Of 9,615 patients, 8,222 (85.5%) were new cases of TB and 1,393 (14.5%) were previously treated cases. Compared with new cases, previously treated cases were significantly more likely to have resistance to one (OR = 2.5,95% CI 2.1-3.0; P < 0.001), two (OR = 4.6, 95%CI 3.7-5.6; P < 0.001), three (OR = 11.5, 95%CI 8.6-15.3; P < 0.001), and four (OR = 18.5, 95% CI 12.0-28.5; P < 0.001) drugs. An approximately linear increase in the likelihood of having multidrug-resistant tuberculosis (MDR-TB) was observed as the total time (measured in months) of prior anti-tuberculosis treatment increased (P < 0.001, chi2 for trend). In multivariate analysis, prior TB treatment for 6-11 months (OR = 7.6, 95% CI 2.6, 22.4; P < 0.001) and > or = 12 months (OR 13.7, 95% CI 4.5-41.6; P < 0.001), but not HIV positivity, was associated with MDR-TB. CONCLUSION: This study shows that prior but ineffective treatment is a strong predictor of drug resistance, and that HIV is not an independent risk factor for MDR-TB. The association between length of treatment and drug resistance may reflect longer treatment as a result of treatment failure in patients with drug resistance; it may also reflect irregular prior treatment for TB, leading to drug resistance.

Adolescent↗
PubMed2000

Standard short-course chemotherapy for drug-resistant tuberculosis: treatment outcomes in 6 countries.

CONTEXT: No large-scale study has investigated the impact of multidrug-resistant tuberculosis (TB) on the outcome of standard short-course chemotherapy under routine countrywide TB control program conditions in the World Health Organization's (WHO) directly observed treatment short-course strategy for TB control. OBJECTIVE: To assess the results of treatment with first-line drugs for patients enrolled in the WHO and the International Union Against Tuberculosis and Lung Disease's global project on drug-resistance surveillance. DESIGN AND SETTING: Retrospective cohort study of patients with TB in the Dominican Republic, Hong Kong Special Administrative Region (People's Republic of China), Italy, Ivanovo Oblast (Russian Federation), the Republic of Korea, and Peru. PATIENTS: New and retreatment TB cases who received short-course chemotherapy with isoniazid, rifampicin, pyrazinamide, and either ethambutol or streptomycin between 1994 and 1996. MAIN OUTCOME MEASURE: Treatment response according to WHO treatment outcome categories (cured; died; completed, defaulted, or failed treatment; or transferred). RESULTS: Of the 6402 culture-positive TB cases evaluated, 5526 (86%) were new cases and 876 (14%) were retreatment cases. A total of 1148 (20.8%) new cases and 390 (44.5%) retreatment cases were drug resistant, including 184 and 169 cases of multidrug-resistant TB, respectively. Of the new cases 4585 (83%) were treated successfully, 138 (2%) died, and 151 (3%) experienced short-course chemotherapy failure. Overall, treatment failure (relative risk [RR], 15.4; 95% confidence interval [CI], 10.6-22.4; P<.001) and mortality (RR, 3.73; 95% CI, 2.13-6.53; P<.001) were higher among new multidrug-resistant TB cases than among new susceptible cases. Even in settings using 100% direct observation, cases with multidrug resistance had a significantly higher failure rate than those who were susceptible (9/94 [10%] vs 8/1410 [0.7%]; RR, 16.9; 95% CI, 6.6-42.7; P<.001). Treatment failure was also higher among patients with any rifampicin resistance (n=115) other than multidrug resistance (RR, 5.48; 95% CI, 3.04-9.87; P<.001), any isoniazid resistance (n=457) other than multidrug resistance (RR, 3. 06; 95% CI, 1.85-5.05; P<.001), and among patients with TB resistant to rifampicin only (n=76) (RR, 5.47; 95% CI, 2.68-11.2; P<.001). Of the retreatment cases, 497 (57%) were treated successfully, 51 (6%) died, and 124 (14%) failed short-course chemotherapy treatment. Failure rates among retreatment cases were higher in those with multidrug-resistant TB, with any isoniazid resistance other than multidrug resistance, and in cases with TB resistant to isoniazid only. CONCLUSIONS: These data suggest that standard short-course chemotherapy, based on first-line drugs, is an inadequate treatment for some patients with drug-resistant TB. Although the directly observed treatment short-course strategy is the basis of good TB control, the strategy should be modified in some settings to identify drug-resistant cases sooner, and to make use of second-line drugs in appropriate treatment regimens. JAMA. 2000;283:2537-2545

Antitubercular Agents↗
PubMed2000

Dynamics and control of the global tuberculosis epidemic.

Studies of disease burden have reaffirmed that tuberculosis is among the top 10 causes of death in the world. The tuberculosis epidemic in most countries could eventually be brought under control by implementing the World Health Organization's (WHO) directly observed therapy, short course (DOTS) strategy, although tuberculosis linked to human immunodeficiency virus (HIV) in Africa and multidrug-resistant tuberculosis (MDR-TB) in the former Soviet Union urgently demand adaptations and extensions of DOTS. Most high-incidence countries have achieved treatment success rates approaching the WHO 85% target in pilot projects. In the long term, we may have better diagnostics, drugs, and vaccines to control the disease; for the next 5 years, the central problem in global tuberculosis control is to expand DOTS coverage in high-incidence countries. Improved case finding and diagnosis, coupled with best-practice short-course chemotherapy, could quickly and dramatically cut the number of years of healthy life lost due to tuberculosis, especially by preventing death.

AIDS-Related Opportunistic Infections↗
PubMed2000

Supervised preventive therapy for latent tuberculosis infection in illegal immigrants in Italy.

In a multicenter, prospective, randomized, open-label study of isoniazid-preventive therapy (IPT) for latent tuberculosis infection, illegal immigrants from countries where tuberculosis is highly endemic were enrolled at two clinical sites in Northern Italy. Of 208 eligible subjects, 82 received supervised IPT at a dose of 900 mg twice weekly for 6 mo (Regimen A), 73 received unsupervised IPT 900 mg twice weekly for 6 mo (Regimen B), and 53 received unsupervised IPT 300 mg daily for 6 mo (Regimen C). Supervised IPT was delivered at either one tuberculosis clinic or one migrant clinic. The probability of completing a 26-wk regimen was 7, 26, and 41% in Regimens A, B, and C, respectively (p < 0.005, Log- rank test calculated using Kaplan-Meier plots). The mean time to dropout was 3. 8, 6, and 6.2 wk in Regimens A, B, and C, respectively (p = 0.003 for regimen A versus either Regimens B or C). Treatment was stopped in five subjects (2.4%) because of adverse events. The rate of completion of preventive therapy for latent tuberculosis infection among illegal immigrants was low. Supervised, clinic-based administration of IPT significantly reduced adherence. Alternative strategies to implement preventive therapy in illegal immigrants are clearly required.

Adolescent↗
PubMed2000

Standardization of antituberculosis drug resistance surveillance in Europe. Recommendations of a World Health Organization (WHO) and International Union Against Tuberculosis and Lung Disease (IUATLD) Working Group.

Surveillance of antituberculosis drug resistance is an essential tool for evaluating the quality of tuberculosis control programmes. Consensus-based recommendations on uniform reporting of antituberculosis drug resistance surveillance data in Europe have been developed by a Working Group of the World Health Organization (WHO) and the International Union Against Tuberculosis and Lung Disease (IUATLD). Laboratories should use standardized methods for testing drug susceptibility with a quality assurance programme including national and international proficiency testing. The proportion of drug resistance, particularly resistance to isoniazid, rifampicin or both (multidrug resistance) among all definite, i.e. culture-positive, tuberculosis cases at the start of treatment is the major indicator of interest. It should be calculated separately among patients treated previously and among those who have never been treated with > or = 1 month of combined antituberculosis drugs. The Working Group recommends that, in countries in which resources allow, laboratories report drug susceptibility test results on all isolates of the Mycobacterium tuberculosis complex. Test results of the specimen at the start of treatment and clinical data from the notification should be linked using a suitable identifier. Results should be presented by calendar year and analysed by age, sex, place of birth, site of disease and sputum smear results. In countries in which a routine system cannot be organized, representative surveys or sentinel systems are possible alternatives. In some countries, the annual prevalence of multidrug-resistant tuberculosis may be estimated through a national laboratory reporting system.

Antitubercular Agents↗