Stopping TB in Europe: some progress but still not there

Comorbidities in the management of patients with lung cancer

Lung cancer represents a major public health issue worldwide. Unfortunately, more than half of them are diagnosed at an advanced stage. Moreover, even if diagnosed early, diagnosis procedures and treatment can be difficult due to the frequent comorbidities observed in these patients. Some of these comorbidities have a common major risk factor, i.e. smoking, whereas others are unrelated to smoking but frequently observed in the general population. These comorbidities must be carefully assessed before any diagnostic and/or therapeutic decisions are made regarding the lung cancer. For example, in a patient with severe emphysema or with diffuse lung fibrosis, transthoracic needle biopsy can be contraindicated, meaning that in some instances a precise diagnosis cannot be obtained; in a patient with chronic obstructive pulmonary disease, surgery may be impossible or should be preceded by intensive rehabilitation; patients with interstitial lung disease are at risk of radiation pneumonitis and should not receive drugs which can worsen the respiratory insufficiency. Patients who belong to what are called "special populations", e.g. elderly or HIV infected, should be treated specifically, especially regarding systemic treatment. Last but not least, psychosocial factors are of great importance and can vary from one country to another according to health insurance coverage.

Standard Genotyping Overestimates Transmission of Mycobacterium tuberculosis among Immigrants in a Low-Incidence Country

Immigrants from regions with a high incidence of tuberculosis (TB) are a risk group for TB in low-incidence countries such as Switzerland. In a previous analysis of a nationwide collection of 520 Mycobacterium tuberculosis isolates from 2000 to 2008, we identified 35 clusters comprising 90 patients based on standard genotyping (24-locus mycobacterial interspersed repetitive-unit-variable-number tandem-repeat [MIRU-VNTR] typing and spoligotyping). Here, we used whole-genome sequencing (WGS) to revisit these transmission clusters. Genome-based transmission clusters were defined as isolate pairs separated by ≤12 single nucleotide polymorphisms (SNPs). WGS confirmed 17/35 (49%) MIRU-VNTR typing clusters; the other 18 clusters contained pairs separated by >12 SNPs. Most transmission clusters (3/4) of Swiss-born patients were confirmed by WGS, as opposed to 25% (4/16) of the clusters involving only foreign-born patients. The overall clustering proportion was 17% (90 patients; 95% confidence interval [CI], 14 to 21%) by standard genotyping but only 8% (43 patients; 95% CI, 6 to 11%) by WGS. The clustering proportion was 17% (67/401; 95% CI, 13 to 21%) by standard genotyping and 7% (26/401; 95% CI, 4 to 9%) by WGS among foreign-born patients and 19% (23/119; 95% CI, 13 to 28%) and 14% (17/119; 95% CI, 9 to 22%), respectively, among Swiss-born patients. Using weighted logistic regression, we found weak evidence of an association between birth origin and transmission (adjusted odds ratio of 2.2 and 95% CI of 0.9 to 5.5 comparing Swiss-born patients to others). In conclusion, standard genotyping overestimated recent TB transmission in Switzerland compared to WGS, particularly among immigrants from regions with a high TB incidence, where genetically closely related strains often predominate. We recommend the use of WGS to identify transmission clusters in settings with a low incidence of TB.

Mycobacterium tuberculosis transmission in a country with low tuberculosis incidence: role of immigration and HIV infection

Immigrants from high-burden countries and HIV-coinfected individuals are risk groups for tuberculosis (TB) in countries with low TB incidence. Therefore, we studied their role in transmission of Mycobacterium tuberculosis in Switzerland. We included all TB patients from the Swiss HIV Cohort and a sample of patients from the national TB registry. We identified molecular clusters by spoligotyping and mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) analysis and used weighted logistic regression adjusted for age and sex to identify risk factors for clustering, taking sampling proportions into account. In total, we analyzed 520 TB cases diagnosed between 2000 and 2008; 401 were foreign born, and 113 were HIV coinfected. The Euro-American M. tuberculosis lineage dominated throughout the study period (378 strains; 72.7%), with no evidence for another lineage, such as the Beijing genotype, emerging. We identified 35 molecular clusters with 90 patients, indicating recent transmission; 31 clusters involved foreign-born patients, and 15 involved HIV-infected patients. Birth origin was not associated with clustering (adjusted odds ratio [aOR], 1.58; 95% confidence interval [CI], 0.73 to 3.43; P = 0.25, comparing Swiss-born with foreign-born patients), but clustering was reduced in HIV-infected patients (aOR, 0.49; 95% CI, 0.26 to 0.93; P = 0.030). Cavitary disease, male sex, and younger age were all associated with molecular clustering. In conclusion, most TB patients in Switzerland were foreign born, but transmission of M. tuberculosis was not more common among immigrants and was reduced in HIV-infected patients followed up in the national HIV cohort study. Continued access to health services and clinical follow-up will be essential to control TB in this population.

Drug-resistant tuberculosis in the European Union: opportunities and challenges for control

Tuberculosis (TB) is a leading cause of death globally. TB had been considered conquered in Europe but has re-emerged as a significant problem, partly because of poor TB control programs and the link with HIV infection, migrants and other vulnerable populations, but also because a mood of complacency led to declining investment in research and public health infrastructure. In the European Union (EU), efforts initiated by the European Academies Science Advisory Council (EASAC) now assess how research can better inform policy development and indicate the gaps and uncertainties in the scientific evidence base. A growing number of Mycobacterium tuberculosis (Mtb) strains are now resistant to the first-line anti-TB drugs, necessitating use of second-line drugs which are more expensive, less effective and more toxic. The presence of extensively drug-resistant (XDR) TB in the EU illustrates that there are problems with TB management and control. In the EU, the aggregated rate of notified TB is approximately 18 cases per 100,000 population (range 4-120 cases/100,000 in different Member States). The highest rates are found in Eastern European countries. Only about half of EU countries routinely perform drug susceptibility testing linked to notification of TB cases. It is important for the European Commission (EC) to network regional reference laboratories to support molecular epidemiology and exchange of data via creation of interactive international databases of Mtb genotypic and phenotypic information. EU countries should help develop TB laboratory services by investing in training and provision of assistance to maintain quality control in neighbouring Eastern European countries. Improved TB care necessitates research across the spectrum to include fundamental and epidemiological science, research and development (R&D) for new drugs, diagnostics, vaccines, and operational research. Total R&D investment in TB by the EC and Member States is low by comparison with the USA despite Europe being on the frontline of the epidemic. Thus, alternative funding models for targeting TB research priorities by the EU are required. Increasing the visibility of TB as a priority issue for the EU requires the scientific community, with the academies of science, as appropriate, to communicate to politicians, healthcare providers, funders and the public at large about the current threat posed by drug-resistant TB. Any global strategy for TB control must also take into account measures to address the social, environmental and economic issues which are inextricably linked with TB. The academies conclude that, overall, the EU has failed so far to respond sufficiently to the global TB threat but can still draw on considerable strengths in its science. The EU also has a humanitarian responsibility to support TB control in developing countries. It remains very important for the EC that neither biomedical research nor investment in health services should become a casualty of the current economic recession.