Eurosurveillance - Volume 25, Issue 1, 09 January 2020

Previously a country with medium tuberculosis (TB) burden, Serbia almost reached a low TB burden during the period 2005 to 2015.

The aim of this study was to analyse the trends in notification rates and treatment success rates as well as to identify predictors of treatment outcomes.

We performed a trend analysis and logistic regression analysis of 17,441 TB cases registered from 2005 to 2015 in all health facilities in Serbia, to identify predictors of treatment success, loss to follow-up and mortality.

From 2005 to 2015, TB notification rate and mortality in Serbia decreased but treatment success remained below the global target. Loss to follow-up was associated with retreatment (odds ratio (OR) = 2.38; 95% confidence interval (CI): 2.08–2.77), male sex (OR = 1.57; 95% CI: 1.39–1.79), age younger than 65 years (OR = 1.37; 95% CI: 1.20–1.51), lower education level (OR = 2.57; 95% CI: 1.74–3.80) and pulmonary TB (OR = 1.28; 95% CI: 1.06–1.56). Deaths were more frequent in retreatment cases (OR = 1.39; 95% CI: 1.12–1.61), male patients (OR = 1.34; 95% CI: 1.19–1.52), those 65 years and older (OR = 4.34; 95% CI: 4.00–5.00), those with lower education level (OR = 1.63; 95% CI: 1.14–2.33) and pulmonary TB (OR = 2.24; 95% CI: 1.78–2.83).

Special interventions should be implemented to address groups at risk of poor treatment outcome.

Annual influenza vaccination is recommended for older adults, but evidence regarding the impact of repeated vaccination has been inconclusive.

We investigated vaccine effectiveness (VE) against laboratory-confirmed influenza and the impact of repeated vaccination over 10 previous seasons on current season VE among older adults.

We conducted an observational test-negative study in community-dwelling adults aged > 65 years in Ontario, Canada for the 2010/11 to 2015/16 seasons by linking laboratory and health administrative data. We estimated VE using multivariable logistic regression. We assessed the impact of repeated vaccination by stratifying by previous vaccination history.

We included 58,304 testing episodes for respiratory viruses, with 11,496 (20%) testing positive for influenza and 31,004 (53%) vaccinated. Adjusted VE against laboratory-confirmed influenza for the six seasons combined was 21% (95% confidence interval (CI): 18 to 24%). Patients who were vaccinated in the current season, but had received no vaccinations in the previous 10 seasons, had higher current season VE (34%; 95%CI: 9 to 52%) than patients who had received 1–3 (26%; 95%CI: 13 to 37%), 4–6 (24%; 95%CI: 15 to 33%), 7–8 (13%; 95%CI: 2 to 22%), or 9–10 (7%; 95%CI: −4 to 16%) vaccinations (trend test p = 0.001). All estimates were higher after correcting for misclassification of current season vaccination status. For patients who were not vaccinated in the current season, residual protection rose significantly with increasing numbers of vaccinations received previously.

Although VE appeared to decrease with increasing numbers of previous vaccinations, current season vaccination likely provides some protection against influenza regardless of the number of vaccinations received over the previous 10 influenza seasons.