Eurosurveillance - Volume 15, Issue 11, 18 March 2010

Since 2008, the European Centre for Disease Prevention and Control has been collecting data from the European Union (EU) and European Economic Area (EEA) on resistance to first- and second-line drugs against tuberculosis (TB). In 2008, the proportion of multidrug-resistant tuberculosis (MDR TB) was 6.0% of the total case load for 25 countries reporting data. Extensively drug-resistant (XDR TB) reporting has increased since 2007 and was observed in 7.3% of the MDR TB cases in 13 reporting countries. MDR TB remains a threat and XDR TB is now established within the EU/EEA borders.

As of 1 March 2010, a total of 11 primary cases with onset of symptoms between 31 December 2009 and 10 February 2010, have been identified with identical hepatitis A genotype IB strains in the Netherlands. A relation with Australian and French foodborne outbreaks occurring in 2009 and 2010 is suspected. Ten of the 11 primary cases indicated that they had consumed one or more products containing semi-dried tomatoes during their incubation period.

A cluster of 14 cases of Salmonella Urbana cases in Finland, the Czech Republic and Latvia were identified in January-February, 2010. The majority of cases (11) were male and children under 16 years of age. The investigation is currently ongoing and comparison of pulsed-field gel electrophoresis (PFGE) profiles of the isolates suggests that the cases may have a common source of infection.

This paper describes the results of second-line drug (SLD) susceptibility tests among multidrug-resistant tuberculosis (MDR TB) cases reported in 20 European countries aiming to identify extensively drug-resistant tuberculosis (XDR TB) cases. A project on molecular surveillance of MDR TB cases was conducted by EuroTB and the National Institute for Public Health and the Environment (RIVM) from 2005 to 2007. Information on drug susceptibility testing (DST) was provided to this project and case-based data on MDR TB cases were reported on a quarterly basis by 20 countries of the World Health Organization’s European Region, including 15 European Union Member States. Data included SLD susceptibility test results, enabling a retrospective description of XDR TB cases notified between 2003 and 2007 .In 18 countries DST was performed for two or more of the SLD included in the XDR TB definition. The proportion of MDR TB isolates tested for SLD varied widely between countries (range 20 to 100 percent). In the 18 countries, 149 (10%) XDR TB cases were reported among MDR TB cases with available DST results for SLD. Sixteen additional MDR TB cases were reported by the MDR TB surveillance system when compared with the number of routinely reported MDR TB cases to EuroTB in ten countries with representative data reported during three consecutive years (2003-2005). To counter the threat of XDR TB in Europe, a standardised approach to XDR TB surveillance and DST for SLD is needed, as well as increased laboratory capacity across European countries.

An analysis of surveillance data was performed to assess treatment outcomes of patients belonging to selected calendar year cohorts. Twenty-two countries in the European Union (EU) and European Economic Area (EEA) reported treatment outcome monitoring data for culture-confirmed pulmonary tuberculosis (TB) cases reported in 2007. The overall treatment success rate was 73.8% for all culture-confirmed pulmonary cases and 79.5% for new culture-confirmed pulmonary cases. For the cohort of new culture-confirmed TB cases, only three countries achieved the target of 85% success rate. This underachievement appears to be a result of relative high defaulting and unknown outcome information. Case fatality remains high particularly among cases of national origin. This factor appears attributable to advanced age of the national cohort. Treatment outcomes for multidrug-resistant tuberculosis were reported by 15 countries, with a range of 19.8% to 100% treatment success at 24 months. The data underline the urgent need for strengthening treatment outcome monitoring in the EU and EEA in order to ensure an effective programme implementation and case management that will ultimately contribute to TB elimination.

To quantify the risk of developing tuberculosis (TB) following school contact with a student with smear positive respiratory TB in a population with a high background rate of tuberculosis, a retrospective cohort study was conducted. This study included all students and staff (n=1,065) at an inner city secondary school in Birmingham, United Kingdom (UK). Being in the same school year as the index case resulted in a significantly higher risk of being diagnosed with active TB (odds ratio (OR) 6.11) and either active or latent TB (OR 10.52) compared to the risk for pupils in other school years. Neither lower level classroom exposure in tutoring groups nor being a staff member resulted in significantly increased risk of infection. The number of cases detected in the school was significantly higher than compared with the TB notification rate for the respective age groups in the population in the area. This study is consistent with the small body of evidence that already exists suggesting that greater levels of classroom contact with a student with smear positive active TB significantly increases the risk of contracting active and latent TB. It also suggests that staff may be at a lower risk of active TB than students. It does not appear that being in an area with high TB incidence substantially alters the epidemiology of the outbreak or risk of transmission between students in comparison to other populations.