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Paul Nunn

Publications and source records attributed to Paul Nunn.

12 recordsLinked to original sources
PubMed2006

Epidemiology of antituberculosis drug resistance (the Global Project on Anti-tuberculosis Drug Resistance Surveillance): an updated analysis.

BACKGROUND: The burden of tuberculosis is compounded by drug-resistant forms of the disease. This study aimed to analyse data on antituberculosis drug resistance gathered by the WHO and International Union Against Tuberculosis and Lung Disease Global Project on Anti-tuberculosis Drug Resistance Surveillance. METHODS: Data on drug susceptibility testing for four antituberculosis drugs--isoniazid, rifampicin, ethambutol, and streptomycin--were gathered in the third round of the Global Project (1999-2002) from surveys or ongoing surveillance in 79 countries or geographical settings. These data were combined with those from the first two rounds of the project and analyses were done. Countries that participated followed a standardised set of guidelines to ensure comparability both between and within countries. FINDINGS: The median prevalence of resistance to any of the four antituberculosis drugs in new cases of tuberculosis identified in 76 countries or geographical settings was 10.2% (range 0.0-57.1). The median prevalence of multidrug resistance in new cases was 1.0% (range 0.0-14.2). Kazakhstan, Tomsk Oblast (Russia), Karakalpakstan (Uzbekistan), Estonia, Israel, the Chinese provinces Liaoning and Henan, Lithuania, and Latvia reported prevalence of multidrug resistance above 6.5%. Trend analysis showed a significant increase in the prevalence of multidrug resistance in new cases in Tomsk Oblast (p<0.0001). Hong Kong (p=0.01) and the USA (p=0.0002) reported significant decreasing trends in multidrug resistance in new cases of tuberculosis. INTERPRETATION: Multidrug resistance represents a serious challenge for tuberculosis control in countries of the former Soviet Union and in some provinces of China. Gaps in coverage of the Global Project are substantial, and baseline information is urgently required from several countries with high tuberculosis burden to develop appropriate control interventions.

Antitubercular Agents↗
PubMed2006

Patients with previously treated tuberculosis no longer neglected.

Over the past decade, global and national tuberculosis (TB)-control programs, challenged with limited resources, have had to prioritize interventions to maximize impact. For this reason, patients with newly diagnosed cases of TB received more attention than did patients with a previous history of treatment. The recently launched STOP TB Strategy and Global Plan to STOP TB 2006-2015 now promote proper diagnosis and treatment of TB for all patients, without distinction of smear status, drug susceptibility, sex, or age, including all patients with a history of previous treatment. Previously treated patients are difficult to re-treat and represent an important source of disease transmission, as well as a serious threat to TB control worldwide, because of their higher rate of drug resistance.

Antitubercular Agents↗
PubMed2006

Global incidence of multidrug-resistant tuberculosis.

BACKGROUND: The global number of incident cases of multidrug-resistant (MDR) tuberculosis (TB) in 2000 was estimated to be 272,906 (95% confidence interval [CI], 184,948-414,295). For accurate planning of TB control programs, this estimate and others have been revised using data from additional countries and by including in the model previously treated TB cases, which had not been accounted for in the previous analysis. METHODS: Multiple logistic regression was used to identify variables that were predictive of MDR-TB frequency among new and previously treated cases surveyed in 90 and 77 countries, respectively. These variables were then used to estimate MDR-TB frequencies in countries that had not been surveyed. RESULTS: The total number of MDR-TB cases estimated to have occurred worldwide in 2004 is 424,203 (95% CI, 376,019-620,061), or 4.3% (95% CI, 3.8%-6.1%) of all new and previously treated TB cases. In the same year, 181,408 (95% CI, 135,276-319,017) MDR-TB cases were estimated to have occurred among previously treated TB cases alone. Three countries--China, India, and the Russian Federation--accounted for 261,362 (95% CI, 180,779-414,749) MDR-TB cases, or 62% of the estimated global burden. CONCLUSIONS: These updated sets of estimates incorporating previously treated TB cases call for an urgent plan to expand appropriate diagnostic and treatment services for patients with MDR-TB in low-resource settings.

Global Health↗
PubMed2006

Towards universal access to HIV prevention, treatment, care, and support: the role of tuberculosis/HIV collaboration.

Tuberculosis is the oldest of the world's current pandemics and causes 8.9 million new cases and 1.7 million deaths annually. The disease is among the most common causes of morbidity and mortality in people living with HIV. However, tuberculosis is more than just part of the global HIV problem; well-resourced tuberculosis programmes are an important part of the solution to scaling-up towards universal access to comprehensive HIV prevention, diagnosis, care, and support. This article reviews the impact of the interactions between tuberculosis and HIV in resource-limited settings; outlines the recommended programmatic and clinical responses to the dual epidemics, highlighting the role of tuberculosis/HIV collaboration in increasing access to prevention, diagnostic, and treatment services; and reviews progress in the global response to the epidemic of HIV-related tuberculosis.

AIDS-Related Opportunistic Infections↗
PubMed2006

Multidrug-resistant tuberculosis management in resource-limited settings.

Evidence of successful management of multidrug-resistant tuberculosis (MDRTB) is mainly generated from referral hospitals in high-income countries. We evaluate the management of MDRTB in 5 resource-limited countries: Estonia, Latvia, Peru, the Philippines, and the Russian Federation. All projects were approved by the Green Light Committee for access to quality-assured second-line drugs provided at reduced price for MDRTB management. Of 1047 MDRTB patients evaluated, 119 (11%) were new, and 928 (89%) had received treatment previously. More than 50% of previously treated patients had received both first- and second-line drugs, and 65% of all patients had infections that were resistant to both first- and second-line drugs. Treatment was successful in 70% of all patients, but success rate was higher among new (77%) than among previously treated patients (69%). In resource-limited settings, treatment of MDRTB provided through, or in collaboration with, national TB programs can yield results similar to those from wealthier settings.

Antitubercular Agents↗
PubMed2005

Tuberculosis control in the era of HIV.

Without HIV, the tuberculosis (TB) epidemic would now be in decline almost everywhere. However, instead of looking forward to the demise of TB, countries that are badly affected by HIV are struggling against a rising tide of HIV-infected patients with TB. As a consequence, global TB control policies have had to be revised and control of TB now demands increased investment. This paper assesses what is being done to address the issue and what remains to be done.

Adolescent↗
PubMed2003

Effects of human immunodeficiency virus infection on recurrence of tuberculosis after rifampin-based treatment: an analytical review.

We reviewed 47 prospective studies of recurrence of pulmonary tuberculosis (TB) after cure to assess the influence of human immunodeficiency virus (HIV) infection and rifampin treatment. Multivariate regression revealed that the recurrence rate for HIV-uninfected persons increased with decreasing duration of therapy: it was 1.4 cases per 100 person-years for recipients of >or=7 months of rifampin therapy and 2.0 and 4.0 cases per 100 person-years for recipients of 5-6 and 2-3 months of rifampin therapy, respectively (trend P=.00014), over a mean follow-up duration of 34 months, at a TB incidence of 250 cases per 100,000 person-years. Relative risks of recurrence associated with HIV infection at these 3 treatment durations were 2.2, 2.1, and 3.4, respectively, with a significant interaction between HIV infection status and treatment duration (P=.025). The recurrence rate increased with the background TB incidence (P=.048), and it decreased over time since completion of treatment in HIV-uninfected but not in HIV-infected patients (overall trend, P=.00008; difference by HIV infection status, P=.025). In countries where HIV infection is endemic, TB recurrence may be reduced by administration of rifampin-based treatment for at least 6 months, in accordance with World Health Organization recommendations.

Antitubercular Agents↗
PubMed2003

How human immunodeficiency virus voluntary testing can contribute to tuberculosis control.

Human immunodeficiency virus (HIV) is fueling the tuberculosis (TB) epidemic, particularly in sub-Saharan Africa. However, despite their close epidemiological links, the public health responses have largely been separate. WHO has set out a strategy to decrease the burden of HIV-related TB, comprising interventions against both TB and HIV. Voluntary counselling and testing (VCT) for HIV can link TB and HIV programme activities. The benefits of VCT for HIV to TB patients include referral for appropriate clinical care and support for those testing HIV-positive. Likewise, people attending a centre for VCT can benefit from TB screening: those found to be both HIV-positive and with active TB need referral for TB treatment; those without active TB should be offered TB preventive treatment with isoniazid. To explore how VCT for HIV can contribute to a more coherent response to TB, WHO is coordinating the ProTEST Initiative. The name "ProTEST" is derived from the Promotion of voluntary testing as an entry point for access to the core interventions of intensified TB case-finding and isoniazid preventive treatment. Other interventions may be added to provide finally a comprehensive range of HIV and TB prevention and care interventions. Under the ProTEST Initiative, pilot districts are establishing links between centres for VCT for HIV and TB prevention and care. This will pave the way for large-scale operationalization of the comprehensive range of interventions needed to control TB in settings with high HIV prevalence.

AIDS Serodiagnosis↗
PubMed2002

The research agenda for improving health policy, systems performance, and service delivery for tuberculosis control: a WHO perspective.

The development of WHO's DOTS strategy for the control of tuberculosis (TB) in 1995 led to the expansion, adaptation and improvement of operational research in this area. From being a patchwork of small-scale studies concerned with aspects of service delivery, TB operational research shifted to larger-scale, often multicountry projects that were also concerned with health policy and the needs of health systems. The results are now being put into practice by national TB control programmes. In 1998 an ad hoc committee identified the chief factors inhibiting the expansion of DOTS: lack of political will and commitment, poor financial support for TB control, poor organization and management of health services, inadequate human resources, irregular drug supplies, the HIV epidemic, and the rise of multidrug resistance. An analysis of current operational research on TB is presented on the basis of these constraints, and examples of successful projects are outlined in the article. We discuss the prerequisites for success, the shortcomings of this WHO- supported programme, and future challenges and needs.

Antitubercular Agents↗